Revisiting the 257 Ackley Improved

[wildcatter]

It's been a while since I enjoyed the 257 AI in Varmint configuration, but I'm about to build another. over 20 years ago I found this to be the best Long Range Varmint rig I have had in my 40 years of shooting at that time. Today, I've had many other calibers in several different actions, but none have impressed me the way the old Bob Imp. did, and now some 30 years laters, I'm going to try and better that one that was so satisfying 30 years ago.

I'm starting with a Savage Axis action, with a special SSS trigger. Then I'll be dressing this rifle in a custom, Laminated Walnut stock, I talked Fred into building altering the layers by changing the direction of the grain 90 degrees every other layer. My thoughts were aimed at stiffness over beauty and keeping weight on the lighter side for a wood stock.

The Barrel is being rifled this week, a 1-10, for lighter bullets that will be throttled up, and open up,,, beyond 600 yards on varmints,,,, I'm not after pelts! It is already deep hole drilled, and is contoured in a Heavy Varmint configuration that is 28" long. The reamer is being modified with a .2495" pilot by Manson as I am typing. I plan on cutting this blank to a finished 27" 6 fluted design, fluting it 3" from the muzzle to 5" from the breech.

I am removing the 10-50x60 Sightron with it's 1/8 MOA dot, and replacing the scope on this rifle with an SIII 8-32x56 PLR w/MOA2 reticle. Perfect for field use for Varmints as far as I can reach out with this rifle.

Brass was being made from Lapua 30/06 brass, but as I have stated before, I prefer 8x57 IS Lapua brass for the XX x 57 cases the 6mm, 257, and 7mm AI chamberings. But I could not find any,,,,, till Saturday, I was able to secure an order for 1 box of 100 I found in Canada. But I found that Monday when it was status changed to shipped, with tracking,,,,,, Canadian Post went on strike Canada wide! Then Monday afternoon, USPS announced they were not taking any shipments to Canada till further notice, as all Canadian Postal is shut down due to this strike!

So I will for now work with the 20 cases I have formed and wait till I receive the 8x57 brass once the strike is settled. Or I will see if they can arrange another shipping method. But 100 cases is enough to wear this new barrel out loading it to the extreme, which is what I built this chambering for. It is the toughest brass I've used from Lapua. The last batch I used for 6mm AI was also the most uniform cases I've had from Lapua, which includes 6.5x47 and 220 Russian! That is saying a lot!

Pictures of components and build updates to come as I get closer to a completed rifle! The fun,,,,,, has begun,,,,

 

[357Mag]

It's been a while since I enjoyed the 257 AI in Varmint configuration, but I'm about to build another. over 20 years ago I found this to be the best Long Range Varmint rig I have had in my 40 years of shooting at that time. Today, I've had many other calibers in several different actions, but none have impressed me the way the old Bob Imp. did, and now some 30 years laters, I'm going to try and better that one that was so satisfying 30 years ago.

I'm starting with a Savage Axis action, with a special SSS trigger. Then I'll be dressing this rifle in a custom, Laminated Walnut stock, I talked Fred into building altering the layers by changing the direction of the grain 90 degrees every other layer. My thoughts were aimed at stiffness over beauty and keeping weight on the lighter side for a wood stock.

The Barrel is being rifled this week, a 1-10, for lighter bullets that will be throttled up, and open up,,, beyond 600 yards on varmints,,,, I'm not after pelts! It is already deep hole drilled, and is contoured in a Heavy Varmint configuration that is 28" long. The reamer is being modified with a .2495" pilot by Manson as I am typing. I plan on cutting this blank to a finished 27" 6 fluted design, fluting it 3" from the muzzle to 5" from the breech.

I am removing the 10-50x60 Sightron with it's 1/8 MOA dot, and replacing the scope on this rifle with an SIII 8-32x56 PLR w/MOA2 reticle. Perfect for field use for Varmints as far as I can reach out with this rifle.

Brass was being made from Lapua 30/06 brass, but as I have stated before, I prefer 8x57 IS Lapua brass for the XX x 57 cases the 6mm, 257, and 7mm AI chamberings. But I could not find any,,,,, till Saturday, I was able to secure an order for 1 box of 100 I found in Canada. But I found that Monday when it was status changed to shipped, with tracking,,,,,, Canadian Post went on strike Canada wide! Then Monday afternoon, USPS announced they were not taking any shipments to Canada till further notice, as all Canadian Postal is shut down due to this strike!

So I will for now work with the 20 cases I have formed and wait till I receive the 8x57 brass once the strike is settled. Or I will see if they can arrange another shipping method. But 100 cases is enough to wear this new barrel out loading it to the extreme, which is what I built this chambering for. It is the toughest brass I've used from Lapua. The last batch I used for 6mm AI was also the most uniform cases I've had from Lapua, which includes 6.5x47 and 220 Russian! That is saying a lot!

Pictures of components and build updates to come as I get closer to a completed rifle! The fun,,,,,, has begun,,,,

Wildcatter -

Howdy !

Sounds like another great project, coming from you !

Who provided the barrel blank, if I might ask ?

Your scope upgrade is eminently sensible.

I agree w/ you about the need to watch the weight on walnut/walnut laminate stocks. I went w/ a heavy target-style
walnut/walnut laminat Bishop stock, on the first varmint rifle Fred Sinclair made for me. I didn't mind the all-up rifle weight for anti-groundhog work, while Fred Nick named the gun
" Super Pig ". Pic below..

Yes...please do keep us postred on your project !

With regards,
357Mag

 

[wildcatter]

Wildcatter -

Howdy !

Sounds like another great project, coming from you !

Who provided the barrel blank, if I might ask ?

Your scope upgrade is eminently sensible.

I agree w/ you about the need to watch the weight on walnut/walnut laminate stocks. I went w/ a heavy target-style
walnut/walnut laminat Bishop stock, on the first varmint rifle Fred Sinclair made for me. I didn't mind the all-up rifle weight for anti-groundhog work, while Fred Nick named the gun
" Super Pig ". Pic below..

Yes...please do keep us postred on your project !

With regards,
357Mag

How did I miss that,, of course I'll let you know. It is also being built by Fred, just not the same, but over 40 years ago, was mentored by the same Fred your was built by. Over the years he has refined a lot of what both once took for granted in rifle building!!

It's being built on a Brux 2.50" bore Heavy Varmint Blank. I ordered it last August from Brux with another 1-10 .237" 6mm Heavy Varmint blank to replace the Krieger that was the only totally unusable barrel I have ever bought in my 70 years doing this!! I lucked out, as Brux cuts 25 cal. barrels ONCE A YEAR, I just ordered at the right time!

Tell me, is that towel protecting the paint on the Challenger,, or the finish on the rifle???

either way, good save, two sweet rides!

 

[357Mag]

How did I miss that,, of course I'll let you know. It is also being built by Fred, just not the same, but over 40 years ago, was mentored by the same Fred your was built by. Over the years he has refined a lot of what both once took for granted in rifle building!!

It's being built on a Brux 2.50" bore Heavy Varmint Blank. I ordered it last August from Brux with another 1-10 .237" 6mm Heavy Varmint blank to replace the Krieger that was the only totally unusable barrel I have ever bought in my 70 years doing this!! I lucked out, as Brux cuts 25 cal. barrels ONCE A YEAR, I just ordered at the right time!

Tell me, is that towel protecting the paint on the Challenger,, or the finish on the rifle???

either way, good save, two sweet rides!

Wildcatter -

Howdy !

I suspect I was trying to favor that well-waxed enamel on
" Old Red " ( 73' 318 automatic ).

Cruisin' the many gravel roads of East Allen Co., working on groundhog " suppression "; kept Old Red perpetually dirty.

There's no practical way to do " Area Denial " on groundhog.
In result, one typically favors a " ballistic solution " to the challenges posed by " Soybeanus Digestus " within the A.O.R.

The rifle shown below, is " Super Pig " after Fred turned-down the barrel, and bedded the barrelled action in a McMillan M40A1. This made the rifle legal wt to compete w/ Savage 112V .222 shooters who were takin' all the varmint class wood over @ Blue Creek. My best friend " Speedo " spanked 'em at the very next shoot, using the my .22-35 Remington wildcat
chambering; also shown.

Didn't mean to hi-jack your post ! My apologies !

With regards,
357Mag

 

[wildcatter]

I have a start, I'll start my load development here, 88 grain Bibbs, and 85 grain Noslers, B Both boat tails, and the Bibs 88 grn will be loaded in the 30/06 brass I've prepped. While the 85 grn Noslers will be loaded in the 8x57 Lapua brass.

Both cases are super strong and will take the heavy loads these bullets will be pushed in without any weakening of primer pockets. I've found the 8X57 IS brass to some of the most uniform and toughest brass I have ever loaded in 6mm AI. I've run 108 grain Hottenstein to over 3400 fps in this case without a problem. I expect the same out of the 30/06 cases.

I had thought about going with the 25x47 Lapua which I would think would be a very accurate platform as well. But in the end, the old Roberts improved was chosen for the added range it will give. Maybe not quite the barrel life, but still quite good compared to a 25/06 or one of the magnums. here are the 6x47 shown next to the Bob AI loaded with the bibbs 88 grain. I'm sure the 25x47 would have great barrel life, but for me the happy medium is in the BOB.


Then the glass I'm going to use on this gun showed up and I am very happy with the decision to go with this scope and reticle over the 10-50x60 currently on the gun now. After testing out the illumination and glass last evening, it will be perfect. The adjustment turrets and zero stop are sweet for a field varmint long range setup, for easily readable adjustments. Then the rings throw lever and level it came with, make it more suitable, and easier to use in field use. As well as the welcome flip up covers for hunting use. Thank you quadracer, it was as nice as you stated!



It looks like even if the barrel and reamer get here in the next week or two. It will be the after the holidays before Fred get's to the fluting and chambering. I need to go form some more 06 cases and do some trimming and even though I'm going with a no turn neck, these Lapua 30/06 cases need neck turning. Forming down into the case body 0n these 30/06 cases, leaves about .006" needing to be removed from the .294" loaded neck dia, to accommodate the .291" neck of this chamber. This should take up some of my time for the next few weeks, the anticipation always intensifies as the components all come together and projects get's closer to completion! Even after 70 years, like a kid in a candy shop,,,, only better!

 

[SongdogHunter]

a truly underappreciated cartridge

 

[wildcatter]

a truly underappreciated cartridge

Indeed, everything the 25/284 is with less throat erosion. The 7x57 AI was another people overlook, which will easily equal anything the 284 winchester will do, even the 7mm/06 (7mm express) and in my opinion a little better as far efficiency goes. The downfall has always been the Rem, Win, Federal, and Norma brass we had to choose from with those case length cartridges. Wildcatting is more than just neck sizing and fire forming, but most want the easier route to improved performance, with 06 and rebated rim 284 cases size bang and load.

I've always enjoyed the extra work to go the extra mile for the add benefits and rewards of the extra work to have cases just as good as those 06 length brass cartridges or the fine brass commercially available for the 284 case chamberings.

almost 30 years since my last 257 AI with these even better cases, better powders, better bullets, and the evolution of reloading techniques, it has to be even better today. I'm definitely going to find out!

 

[wildcatter]

I got home yesterday to find another part of this build sitting on the porch, Thanks to Ray @manson reamers!


This is a the only picture I have currently of the cloak this project will wrapped in. This was after the first coat rubbing in the Boiled Linseed Oil. It now has 5 coats of Boiled Linseed Oil, and has had 2 coats of Defthane Satin finish in the second photo, to show the opposite side layers of walnut, shown with it's Axis siblings. I plan to finish the sanding and coating with a couple more coats of the Satin Defthane. I'll post more pics in better light when finished.

 

[Infrequent Shooter]

great looking stock!

 

[Infrequent Shooter]

I have a start, I'll start my load development here, 88 grain Bibbs, and 85 grain Noslers, B Both boat tails, and the Bibs 88 grn will be loaded in the 30/06 brass I've prepped. While the 85 grn Noslers will be loaded in the 8x57 Lapua brass.View attachment 1611464

Both cases are super strong and will take the heavy loads these bullets will be pushed in without any weakening of primer pockets. I've found the 8X57 IS brass to some of the most uniform and toughest brass I have ever loaded in 6mm AI. I've run 108 grain Hottenstein to over 3400 fps in this case without a problem. I expect the same out of the 30/06 cases.

I had thought about going with the 25x47 Lapua which I would think would be a very accurate platform as well. But in the end, the old Roberts improved was chosen for the added range it will give. Maybe not quite the barrel life, but still quite good compared to a 25/06 or one of the magnums. here are the 6x47 shown next to the Bob AI loaded with the bibbs 88 grain. I'm sure the 25x47 would have great barrel life, but for me the happy medium is in the BOB.
View attachment 1611470

Then the glass I'm going to use on this gun showed up and I am very happy with the decision to go with this scope and reticle over the 10-50x60 currently on the gun now. After testing out the illumination and glass last evening, it will be perfect. The adjustment turrets and zero stop are sweet for a field varmint long range setup, for easily readable adjustments. Then the rings throw lever and level it came with, make it more suitable, and easier to use in field use. As well as the welcome flip up covers for hunting use. Thank you quadracer, it was as nice as you stated!
View attachment 1611467View attachment 1611468
View attachment 1611473

It looks like even if the barrel and reamer get here in the next week or two. It will be the after the holidays before Fred get's to the fluting and chambering. I need to go form some more 06 cases and do some trimming and even though I'm going with a no turn neck, these Lapua 30/06 cases need neck turning. Forming down into the case body 0n these 30/06 cases, leaves about .006" needing to be removed from the .294" loaded neck dia, to accommodate the .291" neck of this chamber. This should take up some of my time for the next few weeks, the anticipation always intensifies as the components all come together and projects get's closer to completion! Even after 70 years, like a kid in a candy shop,,,, only better!

I am challenged here on the ID of the three cartridges. The two on the bottom appear to be different. Would you be kind enough to ID all three cartridges shown, two on bottom and one in background? w bullets seated in each cartridge?

 

[wildcatter]

I am challenged here on the ID of the three cartridges. The two on the bottom appear to be different. Would you be kind enough to ID all three cartridges shown, two on bottom and one in background? w bullets seated in each cartridge?

The bottom right case is a necked down Win 7x57 Mauser case that was shot in my 7x57 AI, I necked it down to 25 cal and seated an 88 grain Bibb HP in it. It has the same headspace as the Roberts AI I am building.

The bottom right is a 8x57 IS Lapua case I previously fired in the 6mm AI I built, I ran my 25 cal K&M neck Mandrel in it and seated an 85 grain Nosler BT in it. The 6mm AI has a shorter headspace by nearly .020", since it was smaller than a 257 AI and I didn't touch the shoulders in the 257 AI dies it did not molest the sharp shoulder, as it never touched them.

But the top case is the 30/06 Lapua virgin brass that was run thru a 7x57 FL mauser die to form the case down. I then ran thru the 257 40* AI Redding Body die to get the neck started down to a 257 neck size. Then it is run thru a Forester 257 AI FL die to size the neck fully down to the 257 and establish the Roberts head space for this die. The body die does not full draw the neck down.

The 30/06 case will need to be fire formed using a load of 14 grains of Bullseye pistol powder with a case full of filler, I'll use generic oatmeal for that. I have used cream of wheat and corn cob media in the past. But since I am moving the neck down into the body of the 30/06, it will be thicker than the chamber of the 257 AI. Once fireformed I can establish the turn to dia to suite my chamber with a loaded round.

A lot of work, but totally worth it, as this brass will take the high pressure I will be loading to and I will never have to worry about stretched primer pockets. A lesson I have found using brass from Winchester, Federal, Norma, and Remington. Those cases wont take three loadings without inconsistent primer pockets from stretching. I am oldy building the Ackly to stand on the cases and take full advantage of the cases in this more modern stronger action. With the 30/06 cases I will wear this barrel out with 100 cases, and never need to make brass for this rifle again.

But I just put the 30/06 brass on hold. I finally found a box of Lapua 8x57IS brass and will simple run it in my FL Redding 7x57 Mauser die and then run thru the 257 Redding body die, and lastly thru the Forrester 257 Roberts AI die. I will use a set my 257 AI die in my press to bottom out on the shellholder with the ram fully raised, then after locking the die, I will remove it and use a .004" PMA die shim under the die and finally run the run the case in the FL roberts AI die I will be using to load this round when the cases are formed.

I will still fire form with the above procedure without bullets and clean the necks up in the neck turner to give me match quality cases for loading. I can't stress how much stronger and uniform the Lapua cases are, I have never fired the 30/06 cases from Lapua in any gun, but I would think it is as good as the 8x57 brass from them. The 6mm AI proved how strong, and uniform they are when I used them in my last 6mm AI, and they are much less work and easier to make.

I just lucked out finding a box of new 8X57 in Canada. But it is taking some time to get as the Canadian postal workers went on strike right when I ordered these. After a week I had to contact the seller and arrange a more expensive shipping method thru Purolator in Canada to get them here. But trust me, this is well worth the wait to get these great cases for my custom build!

 

[Ozzyblu]

What’s your thoughts on the Nosler 257 brass? That is what I am using in my AI.

 

[wildcatter]

What’s your thoughts on the Nosler 257 brass? That is what I am using in my AI.

Depends on how hard your going to push it, and how many times you expect to load it! For me it is a wast of my money, BUT, I am going to stand on these loads, if that was not my intentions, I wouldn't bother with the Ackley chambering and the work I'm going thru to make my brass for this purpose.

I also know from past experience with the nosler in other calibers, that the same loads shot in Lapua cases 221 brass converted to tight neck 17 Mach IV in this instance, with top end loads, some cases as little as 2 loadings, and the third time seating primers, I can feel the difference in seating them. The pockets were not holding up and loose on some of the cases. I found Lapua 221 brass finally, and that is no longer the case after the 3rd and 4th loadings.

I don't think even loading to Book suggested Roberts loads the Nosler will last long enough for 100 cases to were out a barrel. You would have no problem loading the Lapua brass 12 to 15 times with the loads I'm using,,, well into magnum pressures. In my opinion, the Nosler is better than the older Winchester Federal Remington, but they are no where near as bad Hornaday.

I have only witnessed the new Alpha Brass, and not personally used it, but from what I have personally witnessed it may be the closest brass I've seen to Lapua for durability and consistency. But for cartridges based on 7x57 case dimensions, no one comes close to the strength, of the 8x57 IS Lapua brass. But the Lapua is also the hardest to find, and when you can't get the absolute best, it's time to improvise.

My choice was going to be 30/06 and the extensive work needed to make it work, luckily I found a box of new Lapua in 8x57, which as simple as necking down, fire forming, and neck turning. Pretty easy, and in my opinion, the cheapest in the long run as 100 cases is all I'll need for the life of this barrel, using either Lapua option.

 

[std7mag]

Personally, I use PPU (PVRI PARTIZAN) 7X57 Mauser brass for both my 257 Roberts and AI.

You might also want to check out Sierra's 90gr BlitzKing.
Furthest I've really shot them is 400 yards on coyotes.

 

[wildcatter]

Personally, I use PPU (PVRI PARTIZAN) 7X57 Mauser brass for both my 257 Roberts and AI.

You might also want to check out Sierra's 90gr BlitzKing.
Furthest I've really shot them is 400 yards on coyotes.

That is one brass brand I have no experience with in any caliber. How does it compare the strength of the primer pockets compared to Win. Rem, for Me the Win was better than even the Federal and Norma. Like I said after 3 different ventures with different Hornady brass, I've come to the conclusion they need to stick to something they are good at, MAKING BULLETS,, and leave the brass to those that know how to make that.

 

[std7mag]

That is one brass brand I have no experience with in any caliber. How does it compare the strength of the primer pockets compared to Win. Rem, for Me the Win was better than even the Federal and Norma. Like I said after 3 different ventures with different Hornady brass, I've come to the conclusion they need to stick to something they are good at, MAKING BULLETS,, and leave the brass to those that know how to make that.

The PPU brass has done me well thus far.
I probably have about 20 reloadings on the 257 Roberts brass at +P loadings.
Rifle is a Ruger 77 MKII.
Shoot everything from 75gr Sierra HP Varmint through the 120gr Sierra BTHP GameKings.
Favorites are the 90gr BlitzKing for coyotes and 115gr Berger VLD and 115gr NBT for deer.

The AI was built on a Savage 111 with a 24" E.R. Shaw sporter barrel.
Again the 90gr BlitzKing over a charge of RL17 for coyotes.
I still use the 115gr Berger VLD and NBT for deer, but I came across some 120gr Partitions, which I'm trying out this year.

I have 7 reloads on the AI brass so far.
Powders have been RL17 for the lighter bullets and RL19 for the heavier. I've been trying out Vihtavouri N555. Has been doing well also.

 

[wildcatter]

It's pretty available, I might have to buy a bag and give it a try after I get this new 257 up and running.

 

[wildcatter]

OK! It's time, the last component is in my hands! Brux, HV Taper, 29", 1-10 twist arrived yesterday. It looks like a week or two before this thing becomes a rifle.


This project started a year ago with the Stock. Sticking with a Varmint style, laminated hardwood stock. The goal was to make it stiffer! I think we did that, alternating the grain between layers 90 degree to each other. Took a chance that if it were to unsightly, I'd just prime and paint it in Candy Blueberry, and clear it in 2K clear coat. But that turned out to be quite satisfying, as well as functional, after bench testing for deflection.

Now it will be the same goal with the barrel. Yes STIFFER, that is the goal. So after it's cut and chambered, with the headspace set. Fred will orientate the flutes to my eye appealing locations. Really don't have the equipment to to bench test the barrel for stiffness. But everything I've researched says it's not only beneficial to stiffness, but will aid in cooling. If not, it certainly won't hurt it, as this will be a hefty field varmint rig!

After fluting a barrel a few decades ago, thinking I could run a longer HV for LV class and add a little length for my Benchrest rifle at the time, I learned real quick why no one else was doing this! HEAT DISSIPATION! It didn't take long to discover how bad mirage could be! Not the way to run on a bench gun for competition.

But today, on a field varmint rigg, where shots are not going to be several in a short timed period. I should reap all the benefits of it, without suffering the negative consequences!

This is the farthest thing from a target rifle build, "BUT" Itarget rifle accuracy is the goal. If it were for paper or steel competition, a 1-8 or even 1-7.5 twist would have been used. As well as Target bullets. I played this game about 3 years ago, and I was terribly disappointed! I ended up with nothing more than a very accurate tiny hole puncher beyond about 500 yards! Same thing I had with my 1-10 6BR, 500 was about where it's 62 grain bullets quit opening up, and it became a tiny hole puncher.

So the 1-10 is back, only in 25 caliber. I had my best luck over 20 years ago with this round, and trust me, it is devastating on groundhogs out to as far 800 yards. The longest I was able to stretch it's legs back then, but my bullets still did enough damage to drop them right where they were hit.

It might be the first 257 AI I've built since that very first one. But I've learned a lot with several other rounds since then. None did better, and most had the latest and greatest improvements. SO, now 20 some years later this rifle is getting many enhancements that first Bob got. Better stock, better bedding, better barrel, better components.

I say that as we have made big strides in Powder, primers, and bullets in the past 20 years along with the barrels and actions, including timing and firing systems. As this action is highly tuned and timed. The Bolt is tuned and bushed, with the smaller firing pin and calibrated protrusion and inertia. It is made to be stepped on! Period. Maximum accuracy with improved ballistics over anything I previously built on the cartridge.

The brass I so much better, I can't even compare it to what I used in the last one. Todays powders again, even the same 4350 is improved with the formula used to today over 20+ years ago. Primers? I don't know as I never thought there was a difference back then. Even my loading dies, and techniques are much improved over what I used back then.

I'm really expecting a lot, and hope this new build does not let me down. I have to blend long range accuracy and performance, with the long range ability for my projectiles to perform as hunting bullets, all at the same time. Something the 1-8 twist 6mm AI failed miserably at!

Time will tell, and I am only a weak or two from finding out just how well all these little things combined are going to come together! One thing is already for sure, I'm definitely having a ball!!

 

[ISS]

I am going B-I-G on my new 25 caliber LR rifle. A second 257 Banshee. The first one weighed 17+/- pounds with a Premier Reticle boosted 6-18 Leupold. This one will wear a Sightron 10-50x60mm scope, I hope an illuminated Christmas Tree-type reticle; coupled with a good laser rangefinder will allow shots consistently out past 1000 yards on these wily Idaho Rockchucks this spring. I bought 1000 of the Sierra 131gr bullets.
Ice Cream scoop full of H-1000 or Retumbo should do the trick.

Good Luck with your projects,

ISS

 

[wildcatter]

I am going B-I-G on my new 25 caliber LR rifle. A second 257 Banshee. The first one weighed 17+/- pounds with a Premier Reticle boosted 6-18 Leupold. This one will wear a Sightron 10-50x60mm scope, I hope an illuminated Christmas Tree-type reticle; coupled with a good laser rangefinder will allow shots consistently out past 1000 yards on these wily Idaho Rockchucks this spring. I bought 1000 of the Sierra 131gr bullets.
Ice Cream scoop full of H-1000 or Retumbo should do the trick.

Good Luck with your projects,

ISS

Over 100 grains of powder and a 1-8 twist barrel spell disaster for accuracy. I found out the hard way why folks don't use 3800 fps cartridges for accuracy, it don't work. Everyone of those cartridges used for 600 to 1000 yards that are winning matches are doing it around 3100 fps for one reason. Thats what works. But with those heavy bullets, even when you get them to hit what your trying to shoot at 1000 yards with fur on the target,,,, EXPECT a high crawl off and low kill rate.

I did it, I found out why for years we used the term Varmint bullets, and high speeds are what has been used for decades for extreme long range varmint work,,,, THATS WHAT WORKS!

Heavy for caliber DOES NOT. You cannot drive any bullet to that many RPM's and expect the accuracy needed to make hits on 3" to under 4" kill zones. and that is with perfect shots. Plus any marginal shot outside that 3" kill zone, those heavy for caliber bullets are known not to OPEN UP or do anything but work like a drill bit.

In order for a bullet to have enough integrity to take the RPM's generated by a barrel fast enough to stabilize them they need to be thicker heavier jackets, not what a varmint hunter needs. But the sad thing is even when driven fast enough to expand and make any marginal shot effective, that requires closer range, because at the speeds your talking, you will not see .4 moa accuracy, it can't physically happen, the integrity of the bullet won't allow it! If you could, it would require a bullet jacket so heavy to hold up to the forces, stress and heat built getting a bullet spinning this fast you might as well shoot a drill bit!

I won't even debate how inefficient a gain of 4 or 500 fps is when I use 40 to 50 grains of powder to get it. I can run that 131 grain bullet as fast as it is capable of traveling before those groups start opening up, even a 25/06 AI or not will drive them as fast possible without destroying the accuracy this bullet is capable of.

I had trouble accepting this until I spoke with Randy Robinett about what was happening. I blamed the barrel, to light a gun, 14#, you name it! Trust me, Randy can tell you a lot more about what will happen than I can, but I can usure you, a 1-10 twist with a 100 grain bullet will be a lot better varmint or accuracy round that what you are going to try and do. I just can't stress how extreme the failures are for the task your expecting to conquer! PHYSICALLY IMPOSSIBLE!

I am sure I will get flamed by all the therosie conspiracy authorities out there, go ahead. But I'm confident your never going to hear one single person that has tried this, condone it, or even suggest it's possible. It just won't work.

We need a thread in the reloading section on this subject, about the possibility of accuracy with the heavy for caliber bullets, at extreme speeds! Why it is worthless for hunting, target bullets designed for 600 to 1000 yards or more target shooting, cannot possible be efficient varmint bullets. Even less efficient than the bullets, are cartridges that require 50 grains of powder for 400 fps increase in velocity, hell that's enough to give most cartridges in this caliber over 3000 fps.

I'm sorry ISS, but before we waste our time when it's so precious at our age, I have to make it clear what a waste that hole build will be, and the mass failure it is sure to produce!!

I been there,, I done that,, I know, I was a FAILURE!!