John708 .284 project is moving along.

[Rustystud]

About two weeks ago John708 received his lefthanded Savage model 10. This time is wears a nutless, 32' Broughton 1:8, 5C, barrel in light Palma Contour, chambered in .284 Winchester. The action has been squared, and the bolt has been replaced with a PT&G .701 bolt. John has spent a lot of time running the numbers on the .284 with 180 grain Berger. As most of you know John has spent the last 3 years shooting the 6mmBRX. The 6mmBRX has proven to be an excellent 600-1000 yard cartridge. On paper the .284 shoots inside the 6mmBRX with regard to the wind. It will be interesting to see if the .284 proves as effective as the 6mmBRX. It cost more to shoot, the recoil is heavier, the toll on brass and barrels may also prove to be costlier. I am sure John will give this new rifle a true test an keep us informed as he does it.

I would personally like to thank, Charles Ballard and Jerry Tierney for their advice. I would also like to thank Dave Kiff, and Tim North for their help with a reamer and barrel. Both make superior products. Another special Thanks to Paul our moderator and owner of the 6mmBR website for allowing us who love to shoot have such a fine forum to share our knowledge.
Nat Lambeth

 

[chuckgreen]

I hope john708 has a better experience with the .284 than I'm having with mine.

I had been shooting 6.5 Shehane or 300WSM in my 1K light guns for several years but wanted to try the 7mm 180 Berger so had a 284 Shehane reamer made by PG&T, ordered a couple of Broughton 1-9 5C's, had them chambered by a proven gunsmith. About a week ago I hung one on my also proven BAT actioned light gun. I necked up some Lapua brass, carefully turned the necks, fireformed a batch while breaking in the barrel, then cleaned up the necks again and built some of the prettiest rounds I've ever made using H4831, BR2's and the Berger 180's.

Much to my surprise at 200yds,the range that I do load testing) I was unable to get a five shot group much under 1.5 inches????? Over the last few days I've varied seating depths from .020 into the lands to .060 out...best result seemed to be about .010 off the lands. I've tried different charge weights and different powders including H4831, H4831sc, H4350 and RL17. I've tried BR2's and 210M's. I've tried 180 Bergers from different batches. I've tried velocities ranging from 2,825 to 2,975,RL17). Every round was shot over my Chrony. ES has run 9 to 15 and SD's around 4-7. But always about the same result...groups from 1.3in to as wide as two inches! And the rounds are evenly spread within the groups which are nicely shaped...just big.

To make sure it wasn't me or the rifle I swapped the 7mm barrel for a new 6BR Kreiger that the same gunsmith had chambered for me along with the 7mms. Within 30 rounds I had two five shot groups of .326 and .392 at the same 200 yard range with the same rifle and set up except for the 7mm barrel and 180B. The problem didn't seem to be with the rifle and I hadn't forgotten how to shoot, apparently.

So, yesterday I tried one more time. I loaded up another 30 even more carefully prepared rounds and shot two groups each of what seemed to have been the best load with each powder and the 180's. Same result. Low ES and SD but big groups.

My conclusion so far.....Berger 180's are not going to shoot in this particular Broughton barrel at this distance with sufficient accuracy to suit me. My experience has been that if a combo won't shoot five under .50 at 200 then it's not going to be competitive for me at 1K. I'm skeptical of claims that VLD's 'settle down' at more distance as I've shot bug holes at 200 with Berger 210's.

Next step will be to try some 175SMK's and 162 Amax's that I just received in this barrel and then try the other Broughton. But, since the object of this whole exercise was to shoot the 180's Bergers I'm disappointed that I can't seem to get them shooting.

Sorry for the long post. At this point I'm frustrated.

Chuck

 

[Moderator]

Chuck, use the cleaning rod to see if Broughton really gave you a 1:9' twist. Also it might be worth recrowning that 7mm barrel just to see if you can get it to shoot.

I would also be suspicious of the bore diameter based on your report. Get the fatest 7mm bullets you can find and see if they shoot better.

My first concern is the barrel twist rate--whether it's really fast enough.

 

[Rustystud]

Chuck:

John had simular circumstances. It was his loading technique. Groups went from 1.75' to the .4s instantly.

John was getting a donut in his case necks.

I reloaded using the following technique yesterday.

Take a virgin Lapua 6.5 X .284, liberally lube the inside of the neck with a Q-tip and imperial sizing wax.

Expand the neck with a tapered expander not a ball expander.

Fire form the case using only the existing tension.

I seated the bullets touching the rifling.

Check your overall length on the second loading.

I am using a Redding 'S' die with a .312 bushing.

Use the appropriate bushing for your neck diameter.

The .284 needs .002-.004 s of neck clearance.

You might read the Blogs and post by Charles Balard and Jerry Tierney both very experienced with this cartridge.

Your cartridge being Bill Shehanes baby you might talk with Bill.

Nat

 

[chuckgreen]

Thanks. I too was suspicious of the twist rate when I wasn't getting a reasonable result...but...after about 100 disappointing rounds I checked it and it wasn't that. The crown, too, looks fine through my borescope although recrowning is a possibility.

After one more try with two other bullets I'm going to screw on the second barrel and try that. If there is anything inherently wrong with the one I've been testing that should show it up.

I rarely run into problems like this so I guess I should view it as a learning experience...if an expensive one

Chuck

 

[chuckgreen]

Thanks Nat, I will try some new brass and the approach you mention. I've been running just under .004 clearance. My chamber is .313 and the loaded round is just over .309 using a .306 bushing in a Redding FL bushing die.

I don't think I've ever had a problem with donuts so am not too familiar with them,except the sugar coated ones). I'll do a little research and try to find out what I should look for.

Chuck

 

[glo]

I would have to agree with our Editor in Chief about the twist rate, but probably for different reasons.

I built a rifle that shoots both 180 Berger’s and 175SKM’s. The wildcat is ballisticly a 7mm Dakota. It spits out both the bullets at about 2900FPS using about 75gr of H1000. The barrel is 28 inches long made by Pac Nor. I purposefully had the barrel made with a fast 7.5 twist. I know the numbers say an 8.5 twist will stabilize both bullet weights, but I don’t believe it.

I’ve shoot this rifle, F-Class at 1000yd. The bullets make perfect little quarter inch holes showing no signs of over stabilization. At a hundred yards the rifle will shoot little quarter MOA triplets. Again the holes are symmetrical and tight.
glo

 

[heikki02003]

A 1:9 is a very slow twist for the 180's. I'm running 1:9 for the 162's in a .284win. Hornady suggests a 1:8 for the 162's, but I wanted to be able to shoot the odd box of 140's. I bet your barrel,s) will shoot the 162's and lighter bullets.

 

[chuckgreen]

Thanks for the comments. The 1-9 twist is the rate recommended by Berger for the 180's and I've read that some guys are shooting the 180's successfully in 1-9 twists. Mine is definitely 1-9..I checked it again today.

After reading Nat's post and checking the brass I've been using I found that I do seem to have 'donuts' inside the necks of many cases. I had been feeling some roughness and a catch at the bottom of the stroke when I seated bullets using a Wilson arbor die but didn't realize what was causing it. I prepped some new cases today exactly as Nat suggested and am going to try them tomorrow.

Also, I'm going to try to salvage the 50 cases I have been using. I don't have an inside neck reamer so I ran the 7mm expander die into a dozen of these cases and then ran them through the neck turner again. Some brass, apparently pushed to the outside by the expender, was removed from the neck right at the neck/shoulder junction by the neck turner. When I seated some bullets in these cases today the tightness at the base was gone and the bullets seated smoothly with less than half the pressure that had been required before. I'm going to try these tommorrow also and see if this made a difference.

I suspect if I have been shooting cases with donuts then no bullets will shoot until I get the brass problem resolved. All of the bullets I want to try are long enough that the bearing surface is going to contact the donuts. I do have some 162 Amax that I'll try when I get good brass going.

Every time I think I kind of know what I'm doing I find out that I don't :,

Chuck

 

[Rustystud]

Chuck:

Redding use to send a reamer with its forming dies. If you read their website they have a reference to case neck donuts.

There are several ways to skin this cat.

1. Reddings recomendation to me was to buy a .284 full length sizing die,non bushing type). This die has a .306 neck and sizes to the exact neck shoulder juncture. A tapered 7mm,.283) expander is used instead of a ball expander. Redding told me the 6.5 X .284 Lapua brass only has to be sized one time in the non bushing full length sizing die. After the first fire forming shot they recomend the Redding Full Length 'S' type sizing with a bushing causing only .002-.003 of neck sizng.

2. Redding told me the second recomendation was they 'use to reccomend', and that was to ream out the neck removing the donut. the use the appropriate neck sizing bushing.

3. Redding said a 30 caliber expander could be use then the neck sized back with a bushing die. The donut will now be on the outside of the neck. The brass can be neck turned to remove the donut in a lathe or hand turner. I was told this was the least desirable choice.

I was told by Charles Ballard to just expand the necks with a tapered expander or mandrel and fire form the virgin before using a neck bushing on the brass the first time. Charles gives a detalied process he went through loading his brass on this sites 7mm Blog.

Good luck gentlemen
Nat

 

[flatlander]

I've got three 9-tw bbls. chambered for the straight 284 with a .318' neck. They are, in the order I chambered them: PacNor 3-groove finished at 28'; Bartlein & Krieger 4-grooves, finished at 30'. The PacNor has a marked preference for S175MKs, while the other two shoot Berger 180 VLDs a little better than the Sierras. Best groups have been with either N165 or H4831 loaded to give right at 2800fps with either bullet, though I hope with a little more tuning, RL17 will do about as well while giving another 100fps. I'm running plain old WW brass, weight sorted into groups with 1gr variation. Only case prep was neck sizing to iron out dings, then chamfering, and flashhole deburring. I've used F210, BR2, and Wolf LRM primers with about the same results at 1000yds.

From the results I've seen out of these three 9-tw. bbls., there's absolutely no doubt in my mind that they all work fine with 180s.

 

[chuckgreen]

My problem did turn out to be donuts. I shot a couple 200 yd five shot groups with new unformed brass today that I prepped as Nat suggested and both were under an inch. Just unsorted Berger 180's seated right at the lands going out at 2,835fps. Now I can start some load development again.

Apparently I did something to cause donuts to form when I first loaded my original batch of brass. I'm not sure what it was but I know what to look for now.

Thanks to all for the help. This forum is a great resource.

Chuck

 

[o2fish]

Hey Chuck glad to her you got it sorted out.I just got my 284 Shehane build finished.what load are you at with the 180s ?

Scott

 

[chuckgreen]

Scott....I'm afraid I'm going to have to start all over again with load development. Yesterday I shot 55.5 gr of 4831sc with 210m and BR2 primers with the 180's seated right at the lands. They were averaging 2,830fps at 2,800 ft elevation and 78 degrees. Five shot groups around 1 in at 200 were a definite improvement but I want to cut that in half.

Chuck

 

[o2fish]

Chuck
Jim Hardy is useing 57g H4831sc, sounds a little hot but Iam going to try and work up to it.
Speeking of the 180s just touching the lands I measured mine from base of case to bullet tip,it seems to be 3.050,does this seem about right or I have a short throat ??
Scott

 

[chuckgreen]

Scott...my OAL with 180's seated at the lands is 3.226. I'd definitely start much lower with the charge and work up. Chuck

 

[JHardy]

54 grains of H4831SC is a good fire form and starting load for the 284 Shehane. In short, the 284 Shehane loads start about where the straight 284 chambering ends. That being said, always work up carefully.

Favor center,
Jim Hardy

 

[o2fish]

Hello Jim
Have done any more testing with R17 with the Shehane,are now useing this powder or still with H4831sc.
We like hearing your information.
Scott

 

[Rustystud]

I have been waiting 3 weeks for my full lenght .284 sizing die from Redding.

I have been waiting since March for my Hornady Hydrolic forming die. I was told two weeks ago it would be September before I got them. This is after I was first told 12 weeks.

I could order a reamer from Dave Kifff and make my own quicker.

What is this world coming to.

Nat Lambeth

 

[RDavies]

I am also starting to think that maybe in cold weather, the 180gn bullets are not too stable in the 9' twists. In a few of my 9' barrels, I havent been able to get top accuraccy from 180 Bergers, but my 8' twist shot them well at 2800fps.
Have many people here done much cronograph testing with primers in the 284? I have narrowed it down to Russian or CCI BR2 primers with 51-51.5 AR2209,H4350) powder.