I have a 1-13.5 bartlein 6br. Lapua brass NS with a .266 bush and expander ball to straighten any dents in the case neck (redding). 68 gn berger hp fb .010 and .020 off the lands. CCI BR-4 primers with 30.2 gn benchmark. This load has shot some good groups.178,.212, and so on. It will not shot good groups all the time though, sometimes they look like two groups. The bedding is good and the action is stress free. I was shooting today and kept getting frustrated with this load so I shot it over a chrony. It would go 3115, 3119,3114, 3197,3178 fps, for a sd of 27ish fps. I am not set-up to shoot groups and chrono at the same time, but I imagine that 5 shotgroup would look like the ones I shot on paper 3 in a bughole and 2 in a lower hole. What can I do to fix SD and ES. Up powder, I was hoping to see about 3300 fps not 3120ish? Try jamming .010 in to the lands? change primers? I shot two strings of 5 shots and both did the same thing. All components are from the same lot. Any help would be greatly appreciated.
best way to tune SD/ES
- Thread starter AdamJ
- Start date
You have a pretty big jump in velocity in your two groups of shots.
Things to check.
* Case capacity - are they all the same wt. ?
* Neck tension - Are all the bullets seating with the same effort? Work to make this consistent.
* Try seating .020" into the lands - that eliminates seating variations.
* Try some Varget as this is a known good recipe.
Those would be the first things I would look at.
Bob
Things to check.
* Case capacity - are they all the same wt. ?
* Neck tension - Are all the bullets seating with the same effort? Work to make this consistent.
* Try seating .020" into the lands - that eliminates seating variations.
* Try some Varget as this is a known good recipe.
Those would be the first things I would look at.
Bob
All charges weighed, on the money at 30.2. Cases sorted by weight, first time I did this of all my other rifles I reload for, they all have SDs in the 4.xx-8.xx fps. this was my first go with a bushing sizer die, and I was amazed at the consistency when I seated bullets, no tight ones or loose necks they all just felt so consistent of all cartridges I reload for. I will try jamming .010 and .020 and see what that does for the numbers. I tried varget @ 32.5, 33.0, 33.5, and 34.0, but they never really where tight .4-.6" (there was bad mirage that day), never ran them over a chrony. I threw some benchmark in and fired a 5 shot group with 66 barts(.232") and a 5 shot with 68 bergers (.178"), stars must have been aligned right. The varget was a lot better then the results I got with 8208 though.
For sure try 0.010" into the lands. I've tried each bullet (80, 69, 68 Berger, 68 Barts) at 10 off, 20 off, and 10 into the lands. All results were the same. 10 in was the most accurate. Have only tried Varget and H322, and Varget has been better. I've only used BR-4 primers. 450's may be worth a try.
Go to the cci 450 primer, stop shooting benchmark, Try some RL10 powder. Go to a 65-66 gr bullet. All ideas to fix the problem you have.Stop shooting benchmark-i have burned 2lbs of it never with great results.I have shot most powders and have had good groups with most of them but the best is RL10 powder. shoot 30.5grs RL10 behind 65gr v-max or 66gr fowler at 3,500FPS SD 5FPS ,ES 15FPS.GREAT GROUPS.
I agree with Jim, Remember BM is a more temperature sensitive powder (relative to the 2000 series of extreme powders). It meters well so the PPC and BR crowd like it for loading at the range but it is a little harder to keep ES and SD down due to temp variation. Brass is a great conductor of heat. Imagine how hot those shots # 4 and 5 are getting sitting in a chamber even for a few seconds. The spread of velocity you are getting is no doubt jumping you into some vibration nodes at some time. Don't get me wrong BM can give good groups at 100 and 200yards but it needs a little more temperature tuning and shot timing compared to something like VARGET (ADI2208) etc. - If it is new it could also be the barrel heating up and letting bullets go a bit better (like a worn in barrel).
I guess I thought BM was an Extreme powder and was just as temp insensitive as varget. Why is the 450 primers helpful in 6 br, powder charge is relatively small. Is it the fact the flash hole is so small that the mag primer has a more uniform burn of the powder column? I have had great luck with BM in my 223 bench gun, SD of 5.34fps and 1/4 moa accuracy. But each gun is unique I might have to dust of the jug of varget and try it again. FJIM, I have noticed you are a big advocate of 10x, but I don't see any of the 6BR favorite loads on the cart. page use. Not knocking your sucess with it but why has it not caught on with others. No flame intended, just looking for some different ideas. Also is 10x pretty temp insensitive, never shot any reloader powder? I shoot blc-2, varget, and BM in 223 and I have some H4895 left from a previous 308 project and some 8208; with out getting anyother powder which would be a good one to try? Thanks
BoydAllen
Gold $$ Contributor
I don't think that you have a twist problem. What you have is the idea that a particular powder charge should stay in tune all the time. It won't. Sometimes, if your load is right on the edge of an accuracy node, you will get this problem. This is why short range Benchrest shooters load at the range. Give it a try, and for cirminy sakes, try different powder charges when you do. When you have a problem group( You are using wind flags aren't you?) load two tests, one with a little more powder, and one with a little less. One more thing, why can't you shoot groups and chronograph at the same time? You mentioned straightening neck dents. When one of my 6PPC cases gets a dented neck, usually from being dropped, and I have straightened and sized it, it will not group until it has been fired once. This has been my experience. Even though the neck looks perfect, there is something different about it that cannot be seen...except on the target.
BM is not temperature sensitive. It "can" do great things in a 6Br with light pills.
Hate to say it but the easiest way to get rid of daily tuning problems is by going to the top node. The one never seen in reloading manuals.
In all my testing with BM in a light 6BR Rem 7.5's were the primers to use.
Never found any other combo that enjoyed the Rem 7.5's in any cartridge.
Problem with Bm is it burns too clean for most tubes at high velocity. Especially new barrels, even custom.
Add a bullet lube like WS2 to keep bore fouling consistent and it will rock.
Last time I used BM in a 6BR was behind WS2 coated 58V-Max at 3650fps. Bugholes at 200 were quite common if not mandatory.
If I had'nt stumbled upon X-Terminator I might still be using it. X-Term pushes 68 Bergs to 3500+ with ease and accuracy in my 14 twist.
Most folks would say a ball powder like X-Term is temp sensitive. I've found that to be totally false. Spring, summer, fall same load same groups.
After the temp drops well below freezing X-Term does stops shooting. Luckily so do I.
Hate to say it but the easiest way to get rid of daily tuning problems is by going to the top node. The one never seen in reloading manuals.
In all my testing with BM in a light 6BR Rem 7.5's were the primers to use.
Never found any other combo that enjoyed the Rem 7.5's in any cartridge.
Problem with Bm is it burns too clean for most tubes at high velocity. Especially new barrels, even custom.
Add a bullet lube like WS2 to keep bore fouling consistent and it will rock.
Last time I used BM in a 6BR was behind WS2 coated 58V-Max at 3650fps. Bugholes at 200 were quite common if not mandatory.
If I had'nt stumbled upon X-Terminator I might still be using it. X-Term pushes 68 Bergs to 3500+ with ease and accuracy in my 14 twist.
Most folks would say a ball powder like X-Term is temp sensitive. I've found that to be totally false. Spring, summer, fall same load same groups.
After the temp drops well below freezing X-Term does stops shooting. Luckily so do I.
Adam.
The ES/SD came down a lot on my 6mmBR when I started annealing the case necks. I turn my necks and don't use an expanded ball with my dies but I would expect that your brass is getting work hardened with both the resizing and expanding. You might also check the concentricity of your loaded rounds. Expander balls are said to hurt concentricity. My testing showed that lack of concentricity shows up both in MV variation and in group size. I try to keep loaded round runout under 0.001 inches.
The ES/SD came down a lot on my 6mmBR when I started annealing the case necks. I turn my necks and don't use an expanded ball with my dies but I would expect that your brass is getting work hardened with both the resizing and expanding. You might also check the concentricity of your loaded rounds. Expander balls are said to hurt concentricity. My testing showed that lack of concentricity shows up both in MV variation and in group size. I try to keep loaded round runout under 0.001 inches.
Adam I had proublems like yours on a rifle. I pulled and trimed the extractor spring so the brass would lay in the rifle when extracted. this eliminated the dings in the neck of the fired case. Then pull the resizing ball and just use the bushing when resizinng. You will have much better and consistent neck tenchion.
Hope this helps.
Terry Pohl
Ps. Please forgive the spelling, could not find the spellcheck.
Hope this helps.
Terry Pohl
Ps. Please forgive the spelling, could not find the spellcheck.
i have had good luck with BM in .223 also groups in .260-.350 .
I dont know why i cant get some one else to try the RL10 power on here. THREE rifles have all shot it the same,all were 14 twist. with light bullets. I like to try different loads and have shot just about every powder and bullet that you can from a 14 twist gun.30.5 grs RL10 behind any good 65-66 gr bullet will give you the benchrest accuracy we seek,it can be tune up & down for temp but its not senistive, say 28.5gr to 31.0 gr shoots well.If you try it im sure you wont be disapointed and maybe if we get enough people to try it we can get it posted. my new load is 33.8grs of IMR8208 behind a 70gr SBK at 3,550FPS groups are poor at .450ish but in the ground hog fields its been unreal.The holy grail of varmit loads.
I dont know why i cant get some one else to try the RL10 power on here. THREE rifles have all shot it the same,all were 14 twist. with light bullets. I like to try different loads and have shot just about every powder and bullet that you can from a 14 twist gun.30.5 grs RL10 behind any good 65-66 gr bullet will give you the benchrest accuracy we seek,it can be tune up & down for temp but its not senistive, say 28.5gr to 31.0 gr shoots well.If you try it im sure you wont be disapointed and maybe if we get enough people to try it we can get it posted. my new load is 33.8grs of IMR8208 behind a 70gr SBK at 3,550FPS groups are poor at .450ish but in the ground hog fields its been unreal.The holy grail of varmit loads.
FJIM
Don't get offended.
I've tried 10X in the 204R several different times. Always the same result.
Great accuracy that is followed by excessive hard black carbon in the throat leading to terrible accuracy. Usually at the 40 - 50 rd mark everything goes nuts. Whole lootta scrubbing to get it out.
For my needs thats unacceptable. W-748 in the same barrel will go 400+ rds naked bullets with only neglible accuracy loss.
The Pac-Nor 14 twist 6BR barrel I have now was bought used on the web. Gentlman who owned it before me used 10X in it. When it arrived I ran a patch of Hoppes through it to clean out the paper packing dust. Then a dry patch to dry it.
Held it up to the light to see what I could see. Even without a bore scope I could see the first 6" of the bore was black.
I scrubbed, brushed, soaked, JB'd and even used a little bit of 600grit paste on that throat.
Took me many nights to get it shiny inside. Yep, No bore quide, I know the illegality of that.
Maybe it was me but it took a lot of rds for that tube to settle down afterwards. Most accurate barrel I own at the present time. Outshoots my PPC.
Thats why I refuse to use 10X. Lots of folks like it in the 204R but I'd quess they scrub frequently.
Don't get offended.
I've tried 10X in the 204R several different times. Always the same result.
Great accuracy that is followed by excessive hard black carbon in the throat leading to terrible accuracy. Usually at the 40 - 50 rd mark everything goes nuts. Whole lootta scrubbing to get it out.
For my needs thats unacceptable. W-748 in the same barrel will go 400+ rds naked bullets with only neglible accuracy loss.
The Pac-Nor 14 twist 6BR barrel I have now was bought used on the web. Gentlman who owned it before me used 10X in it. When it arrived I ran a patch of Hoppes through it to clean out the paper packing dust. Then a dry patch to dry it.
Held it up to the light to see what I could see. Even without a bore scope I could see the first 6" of the bore was black.
I scrubbed, brushed, soaked, JB'd and even used a little bit of 600grit paste on that throat.
Took me many nights to get it shiny inside. Yep, No bore quide, I know the illegality of that.
Maybe it was me but it took a lot of rds for that tube to settle down afterwards. Most accurate barrel I own at the present time. Outshoots my PPC.
Thats why I refuse to use 10X. Lots of folks like it in the 204R but I'd quess they scrub frequently.
well i never knew that about RL10 i been shoting it for 6 years but i very seldon shoot more than 15 rounds before i clean and never over 25. so never ran into that problem. just a few patches,a few brush passes and im done. i have burned 3 lbs of it in this barrel. and up over 1000 rounds now(on the barrel) and my accuracy is falling off when i could group in the low one's with it allways now im mid one to two's at best.
all i can tell you fellows is it shoots and a friend of mine who is a N135 guy has tryed it and it shot great in his rifle as well, so it seem to shoot. I would think with as many shooters who read this or seen the targets i posted someone would be willing to try it and prove or disprove me.(targets back on page 4 0r 5) if you tell me a brand powder that shoot groups in the one"s consistantly as RL10 does i would spend the $22 bucks to give it a try, allways looking for something that shoots better. yea and dont say PPC,im a 6BR guy because i have owned 5PPC rifles and was never satisfied with any of then,then i built a 6BR and have been happy ever since. im 10years PPC free.
all i can tell you fellows is it shoots and a friend of mine who is a N135 guy has tryed it and it shot great in his rifle as well, so it seem to shoot. I would think with as many shooters who read this or seen the targets i posted someone would be willing to try it and prove or disprove me.(targets back on page 4 0r 5) if you tell me a brand powder that shoot groups in the one"s consistantly as RL10 does i would spend the $22 bucks to give it a try, allways looking for something that shoots better. yea and dont say PPC,im a 6BR guy because i have owned 5PPC rifles and was never satisfied with any of then,then i built a 6BR and have been happy ever since. im 10years PPC free.
FJIM, I have tried 10X in my .222 with good results. I ran through the pound I had, and have a lot of other powder on hand that works just as well, so I haven't bothered to get any more.
I was using 21.5grs and getting 3050fps with a 50gr Nosler BT, with great accuracy as well.
23.5grs with a 40gr BT produced 3375fps.
I had never experienced any carbon fouling with it myself, so I can't comment on that.
I like most of the Reloader line that I have tried, as it has always worked well for me.
I was using 21.5grs and getting 3050fps with a 50gr Nosler BT, with great accuracy as well.
23.5grs with a 40gr BT produced 3375fps.
I had never experienced any carbon fouling with it myself, so I can't comment on that.
I like most of the Reloader line that I have tried, as it has always worked well for me.
adamj, we need to Quit the B.S and try to answer some of your questions. i know nothing about powder other than how to weigh it and dump it in the case. the CCI 450 primer has a flame front that the BR case likes.i think it has to do with the body diameter.seems to give it a good burn. the 450's seem to work best.thats not to say you cant have a load that likes or works with another primer. but the 450 works. you need to get the velocity up into the 3,400FPS range to shoot bug holes i have found that 3,450 to 3,550 FPS range seems to be where most bullets in slow twist will start humming.most benchrest shooters (PPC) the ones that are winning will be 3,400 FPS range with a 68gr bullet. from experience if you are in 3,100 or 3,200FPS range it just does not work well. i have shot good groups with 70gr bergers at 3,300FPS. if you go to the 450 primer get the speed up you should loose the big ES. I have shot good groups H4895. H335 is good powder i have used in the 33.5gr area with 65gr bullets.(3,450FPS). but there was that can of RL10 powder so i bought it worked up a load and was blown away how well it shot in my wore out 6BR. so when i got my new 6BR after initial fireforming my cases(H322) and barrel break in i went right to my load of RL10 and they were in the ones so i have never looked back. but i still try different stuff all the time and have different loads for varmits, targets and so on.
Thank you for all the replys, I am waiting on some more berger bullets and am leaving on a trip so I won't get anything loaded til sunday. I am going to try to bump up to the next velocity node with BM and see what the numbers look like and see if the groups settle down some. I am not getting alot of dented necks maybe one or none out of 30 and it is slight. I clean and lube the case necks before resizeing. If the bm don't work I will try some varg, probably try some 450 with each load. How much should I back down when/if I switch to 450s? If that don't work I just might scrunge up some 10x. I don't clean as often as 15-20 rds more of a 50-75 rds, sometimes more if accuracy is stellar. I hope that the 10x is not a carbon slinger as one post replied that it is. cheers
AlNyhus
Silver $$ Contributor
AdamJ, my assumption here is that you're shooting over windflags of some sort...so bearing this in mind here's my suggestion, in this order:
- Stay with the 68 gr. Berger at this point.
- Set the seating depth for a solid 'jam'. Adjusting the seater .020 shorter than 'just touching' works fine. Do this first and leave it there until you've done the rest.
- Start with a neck bushing .003 smaller than what the necks measure across the pressure ring of the bullet.
- Benchmark works pretty well in the 6BR with the 65-68 gr. bullets, but you're going to need to increase the powder charge from where you're at. Incremental increases of .5 gr. work well.
- N135 really works in the 6BR's with these bullet weights in the 3350-3400 range. You'll be in the 33.0-34.0 range when this powder really comes alive.
- The new XBR8208 is working well. It's basically interchangable with N135.
With the seating depth set and the .003 neck bushing, tune the gun with the powder measure...going up .5 gr. at a time and shooting 3 shot groups until it either shoots 'em in a hole or the bolt gets sticky. If it's not shooting when the bolt gets sticky and/or you see obvious pressure signs, change powders and start back up with the charge weights...again in .5 gr. increments. Repeat this until you find a powder it likes. Then, shoot several 5 shot groups with that powder charge to verify it's consistency.
After you've found the powder it likes, then you can change seating depth in .010 increments.
Then tinker with neck tension..up/down. Don't be surprised if more neck tension works better.
The 'double grouping' you're seeing is not due to the velocity differences. Don't waste your time and/or components going down that road and following that old wives tale.
Again....you need to base all this on shooting over some sort of windflag setup as step #1.
Hope this helps.
Good shootin'.
-Al
- Stay with the 68 gr. Berger at this point.
- Set the seating depth for a solid 'jam'. Adjusting the seater .020 shorter than 'just touching' works fine. Do this first and leave it there until you've done the rest.
- Start with a neck bushing .003 smaller than what the necks measure across the pressure ring of the bullet.
- Benchmark works pretty well in the 6BR with the 65-68 gr. bullets, but you're going to need to increase the powder charge from where you're at. Incremental increases of .5 gr. work well.
- N135 really works in the 6BR's with these bullet weights in the 3350-3400 range. You'll be in the 33.0-34.0 range when this powder really comes alive.
- The new XBR8208 is working well. It's basically interchangable with N135.
With the seating depth set and the .003 neck bushing, tune the gun with the powder measure...going up .5 gr. at a time and shooting 3 shot groups until it either shoots 'em in a hole or the bolt gets sticky. If it's not shooting when the bolt gets sticky and/or you see obvious pressure signs, change powders and start back up with the charge weights...again in .5 gr. increments. Repeat this until you find a powder it likes. Then, shoot several 5 shot groups with that powder charge to verify it's consistency.
After you've found the powder it likes, then you can change seating depth in .010 increments.
Then tinker with neck tension..up/down. Don't be surprised if more neck tension works better.
The 'double grouping' you're seeing is not due to the velocity differences. Don't waste your time and/or components going down that road and following that old wives tale.
Again....you need to base all this on shooting over some sort of windflag setup as step #1.
Hope this helps.
Good shootin'.
-Al
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