You benchrest guys; Any solutions for different powder lots that shoot different?

[CubCouper]

If it is the same rifle, barrel, rest setup, bench setup, and all that has changed is the powder lot, then I definitely would not look to blame the bedding or equipment issues.

Wind is always a factor, but it sounds like you have been testing in reasonable conditions. Temperature changes can make a tune shift a bit too. Just something to know.

All else being perfect (it never is of course), I'd look to the shape of the group for clues. In the BR world a rifle that is 'almost' perfect will show a sequence of group shapes
1) a couple bullets of vertical (load could be hotter, up a touch, fireball=.1-.2gr)
2) then more horizontal that the wind should give... (wind sensitive... a tiny touch hotter yet, fireball=.05 - .1gr more)
3) round-ish or triangular shaped groups -- probably the most forgiving tune!
4) up a tiny touch more and the groups can get really tiny -- one bullet hole! But these are usually seen as on the edge of being too hot, and a slight change in environment will make weird things happen, like...
5) next notch is 4-and-1 or 3-and-2 groups, where it'll put three or four bullets in one hole, then pitch one. Shooters usually say 'I pulled that one', but there is a good chance that the load is too hot. Go down a tiny touch.
6) The Blow Up -- where no bullets touch. You're exactly between accuracy nodes. Either go up a couple tenths or down a couple tenths depending on how close to max you are running.

Just from looking at the groups above, I'd try a couple different approaches: either 18.3 and 18.4 to see if it tightens up, or 18.2 and let the seating depth out .003 to .005. Both changes have the same effect of bumping start pressure to get from #2 to #3 above. Which one works better depends on what the gun likes!

 

[Ccrider]

@VaniB, or that group could be the result of poor gun handling.

 

[AlNyhus]

In another thread a guy thinks my bedding is the problem. He looked at both the photos and he sees horizontal in both my groups. LOL.

And there you have it....

-Al (aka: "a guy")

 

[VaniB]

Cb,

Thanks a lot for all that info! You're swell.

Ccrider,

I've considered that my style of hold is not traditional like a lot of BR competitors. But then I shouldn't be going from a 1/2" tight cluster in one group, to my next group being wide open and horizontal. If my hold was bad, I should have trouble shooting 1/2" 5 shot groups. I have known all along to keep things consistent in benchresting including my hold. Thanks.

Al Nyhus,
Didn't mean any disrespect by referring to you as " a guy on another forum" as much as I simply didn't want to be mentioning anybody by name behind their back if they weren't here to offer their own replies, point of view, assessments, etc. Thanks.

 

[Webster]

I just spent a combined 40 hours at my bench & the range refining handloads for my Rem 700 LVSF 221 Fireball. I'm almost out of a 11year old can of Reloader 7 and switched over to a new can of RL7 I bought last month. The old can gives me 5-shot tight 1/2" cluster groups & it was made here in the USA. The new 1lb RL7 can of powder is Swedish and shoots a scattered 7/8" group. The different countries of manufacture was a rude surprise when I read the label, and I said to myself "uh...oh". The granules doesn't look exactly the same either. (Yes, I'm aware of 4-5lb cans, but I don't compete, and a 1lb can last me 20-40 years. lol)

My question to you accuracy/target shooter guys is if I can expect those 1/2" groups to be lost forever. Or is it usually just a matter of tweaking the powder charge weight or changing the primer to try and get the same fine 1/2" accuracy that I had before? What's your own experience with this?

Tony Boyer says he can find a good load with 30 shots.

 

[VaniB]

Went back again to the range to test more loads with the new can of Swedish RL7 powder. I discovered that much of the problem I was having was due to the bullet being jammed hard into the lands. The new Swedish powder prefers the 40Vmax be off the lands about .0018" and is shooting 4 shot 7/16" groups which is as good as the groups I was doing with my old USA made RL7 powder. Also testing LiLGun with promising results. Probably just go back with the Swedish made RL7 as my main go to powder for the 221 Fireball, being it's less temp sensitive/finicky then LilGun is reported to be.

ETA; The only difference besides changing the OAL length of the cartridge with 40Vmax from 1.930" down to 1.912" is that the USA powder does the 1/2" groups with 18.2 grams, while the Swedish powder does 1/2" groups with 18.6 grams.

 

[Dusty Stevens]

Tony Boyer says he can find a good load with 30 shots.

How many times over a weekend match do you think he chages that though? 15-16 times over 20 groups?

 

[BoydAllen]

If I were looking at an entirely different powder manufacturer, I would assume that I needed to do a new workup. The thing that I don't get is the hours and hours thing. I take my cleaning and reloading stuff to the range, and for a varmint rifle, a chronograph, and will have finished the whole investigation in a couple of hours, three at the most. Weigh bullets for 100 yard load testing? Why? I am always amazed at how complicated a LOT of people want to make working up a load with one powder and bullet. Did you simply duplicate the old powder charge and seating depth and decide on that basis that there was a problem? I admit that I skim, so I may have missed something. For short range group competitors, loads are a very fluid thing.

 

[VaniB]

If I were looking at an entirely different powder manufacturer, I would assume that I needed to do a new workup. The thing that I don't get is the hours and hours thing. I take my cleaning and reloading stuff to the range, and for a varmint rifle, a chronograph, and will have finished the whole investigation in a couple of hours, three at the most. Weigh bullets for 100 yard load testing? Why? I am always amazed at how complicated a LOT of people want to make working up a load with one powder and bullet. Did you simply duplicate the old powder charge and seating depth and decide on that basis that there was a problem? I admit that I skim, so I may have missed something. For short range group competitors, loads are a very fluid thing.

As for your NOT weighing bullets; I'm surprised to hear you say you don't do it for testing too. I wish to be able to choose a powder and load based on the tightest group I'm seeing on paper. Sometimes the groups compare to be an 1/8" group smaller or larger and I don't want to wonder if it's because a bullet or two weighed more. And yes, I also set up 3 wind flags during testing. To each his own.

Thanks for the input. The firing range I attend is located in the suburbs of Houston, an area with 3 million people. During cease fire people's rifles can and do get lifted from the rifle-rack and stolen when one goes downrange to hang his target. (I use a cable lock on my unattended rifle to prevent theft) It is not practical for me to set-up a reloading bench away from the firing line where I can't watch my belongings. About 15 years ago I did buy an extra press, sturdy folding table and scale to do this, but I had no peace of mind about theft I never did it again. So then, for the first trip to the range with a new rifle I do sight-in and try different powders. On the 2nd trip I do the "ladder testing" with the most accurate powder results I discovered on the 1st trip. 3rd trip I try different seating depths. 4th and final trip, I try different primers with chosen powder and chosen seating depth that was determined on previous trips. Sometimes, I make an additional trip or 2 to retry & confirm loads.

 

[jimmymac]

I think I'd find a range farther away where reloading on the spot can be done without fear of theft. It would save time in the long run.

 

[BoydAllen]

As for your NOT weighing bullets; I'm surprised to hear you say you don't do it for testing too. I wish to be able to choose a powder and load based on the tightest group I'm seeing on paper. Sometimes the groups compare to be an 1/8" group smaller or larger and I don't want to wonder if it's because a bullet or two weighed more. And yes, I also set up 3 wind flags during testing. To each his own.

Thanks for the input. The firing range I attend is located in the suburbs of Houston, an area with 3 million people. During cease fire people's rifles can and do get lifted from the rifle-rack and stolen when one goes downrange to hang his target. (I use a cable lock on my unattended rifle to prevent theft) It is not practical for me to set-up a reloading bench away from the firing line where I can't watch my belongings. About 15 years ago I did buy an extra press, sturdy folding table and scale to do this, but I had no peace of mind about theft I never did it again. So then, for the first trip to the range with a new rifle I do sight-in and try different powders. On the 2nd trip I do the "ladder testing" with the most accurate powder results I discovered on the 1st trip. 3rd trip I try different seating depths. 4th and final trip, I try different primers with chosen powder and chosen seating depth. Sometimes, I make an additional trip or 2 to retry & confirm loads.

On the bullet weight thing, sounds like you might need to do some verifying of your theory. One thing that you might try looking at, with production bullets, especially if you are seating into, or close to the rifling, is the ogive to base dimension. On the thievery issue, it sounds like your situation would benefit from having a shooting buddy for range excursions, so that you could take turns keeping an eye on things. One could post targets for both, etc. As far as measuring groups goes, I either use a dial caliper, and measure out to out minus true bullet hole diameter, or use a specialty tool like the ones that are used at group benchrest matches, my point being is that I too look at small differences. Good luck with your quest. If I were not loading at the range, I would first do a powder charge test with bullets seated .006 to .010 longer than touch, with some fouler rounds to start, and to use after cleaning. I would test over flags, on a morning or late afternoon when the wind was light and steady, two shots per load, with each pair shot as rapidly as possible. I would load well up over the manual, and be prepared to stop at the first sign of pressure, putting the remaining loads aside for disassembly and resizing. I always take a temp./ humidity gauge to the range and record those when I get up to a max load. After a powder charge has been selected, if I were not loading at the range, I would load up a number of those rounds with the bullets seated long, and take some means to seat them shorter with me to the range. It does not take me long to set up my portable loading equipment, and I generally post enough target centers so that I only have to go down range once at the beginning, and once at the end. If I set up after posting my target, and put things away before retrieving it, I am not leaving equipment unattended. For those with lower power scopes, taking a spotting scope is an important part of the process.

 

[VaniB]

I guess we all have our own methods for arriving at our tight groups and chosen loads. I personally also find it easier to control my handloads when I'm in my comfort zone and designated place for it.

On the bullet weight thing, sounds like you might need to do some verifying of your theory. One thing that you might try looking at, with production bullets, especially if you are seating into, or close to the rifling, is the ogive to base dimension. On the thievery issue, it sounds like your situation would benefit from having a shooting buddy for range excursions, so that you could take turns keeping an eye on things. One could post targets for both, etc. As far as measuring groups goes, I either use a dial caliper, and measure out to out minus true bullet hole diameter, or use a specialty tool like the ones that are used at group benchrest matches, my point being is that I too look at small differences. Good luck with your quest. If I were not loading at the range, I would first do a powder charge test with bullets seated .006 to .010 longer than touch, with some fouler rounds to start, and to use after cleaning. I would test over flags, on a morning or late afternoon when the wind was light and steady, two shots per load, with each pair shot as rapidly as possible. I would load well up over the manual, and be prepared to stop at the first sign of pressure, putting the remaining loads aside for disassembly and resizing. I always take a temp./ humidity gauge to the range and record those when I get up to a max load. After a powder charge has been selected, if I were not loading at the range, I would load up a number of those rounds with the bullets seated long, and take some means to seat them shorter with me to the range. It does not take me long to set up my portable loading equipment, and I generally post enough target centers so that I only have to go down range once at the beginning, and once at the end. If I set up after posting my target, and put things away before retrieving it, I am not leaving equipment unattended. For those with lower power scopes, taking a spotting scope is an important part of the process.

I guess we all have our own methods for arriving at our tight groups and chosen loads. But as it turns out, I do much the same procedure as you do; If I have 8 test loads for the day, then each test load is numbered to correspond to the target. I put eight 1/4" red sticky dots onto one large paper target and number each dot with the numbers from #1 to #8 to correspond to my notes. This way when I'm done for the day, I can study each numbered target to each numbered test load I recorded in my notes. I don't know what serious target shooter doesn't own a spotting scope, or not own a quality front rest with an assortment of interchangeable tops and different rear leather bags to choose from.


Besides theft concerns at the range, I also didn't like having to bring a large 3 sided box along with me to fit around the powder scale to prevent the breeze from blowing the beam. Never mind worrying about surprise rain or drizzle. I personally prefer to be in my comfort zone and home laboratory with more control of what I'm handloading and don't miss the couple of times I tried developing test loads at the range.



You can see the targets with the red dots in the lower right corner of the photo I was referring to. I have my handloading room set up with my ohaus powder scale, trickler, and Sinclair run-out gages all on shelves at perfect eye-level for my height. There is no hunching down, rain, wind, or theft at the range to contend with. Just my personal preference.

 

[BoydAllen]

You may have missed the thread, but thanks to an earlier post in another thread I have a remarkable little scale that cost almost nothing, that works better than one that I had thought was pretty good. Wanting to do some load development at the range with powders that were beyond my skill to throw to the standards that I require, having discovered that I could reliably pinch trickle with it, I came up with this. With it I can do a complete cycle of throw light, trickle, and dump in a funnel in under 30 seconds, to better than +-.05 gr. A couple of decades before I came up with an enclosure for a balance beam scale that included a trickler that one could control with the wind box closed.



http://bulletin.accurateshooter.com...ters-scales-when-reloading-at-outdoor-ranges/

 

[VaniB]

That's neat! As you know, having a near perfect scale takes research and then some perseverance to obtain. Looks like you've found it!

I started with a 10-10 scale that I bought over 40 years ago when I was green and still learning. It was never better then +- 1/10gr accuracy, and sometimes it threw charges worse then that! As I got more into precision custom barrels & handloading and started learning more, I knew I needed better. In recent years, I bought an additional 4 Lyman M-5 scales from 4 different people on ebay and GunBroker, and kept the 2 most accurate of the 5 scales. The scale see on the shelf in that photo I posted has a beam that is sensitive enough that it can be seen moving when i drop a single kernal into the pan. Nirvana!

With the collection of rectal exam devices you and I use, it's getting harder for us to come up with excuses for a bad day at the range. LOL.