FINALLY(maybe) I Hope

As most know I have been going through quite a bit of frustration with a 308, and am thankful for all the advice obtained here(considered most).
After pulling my hair out and spending more time and money(buying more reloading tools) than should ever be required for a good load I may have found it.I had to take a couple weeks off due to a death in the family but finally got back to this nightmare and loaded some rounds with 42.8 & 43 grns of IMR 4895 at 2.740 & 2.773. The 2.740 were worse than dismal @ 200 yards and I thought that this was it the barrel was heading south. Then I shot the 2.773 which is 0.002 shorter than Sierras OAL and the first five shots went into one ragged hole(42.8 grns) the second group 43 grns. not so good around 1 1/2" still better than most.
Now it maybe time to load up a box of this load and give it one final try before saying it is good to go. The round ended up being , brass trimmed to 2.013,Sierra 155MK,CCI LR,IMR4895 @ 42.8grns.,this will get loaded today and shot tomorrow and results will be coming good or bad.
Wish me luck .

Well I went back ro the range today and after loading 25 rounds of 42.8grns.@ 2.773 all done precise checking everything twice all I can say is I give up.Ten rounds and it looked like a shotgun pattern again.
I am calling NSS and ordering a different barrel it will be cheaper in the long run. This barrel would not shoot as a 30br and it will not shoot as a 308 and after $650 between the barrel cost the cost of powder,bullets,primers, not to mention time and gasoline expenses it just isn't worth it anymore.Maybe I will try another time.
Hopefully Jim has one in stock and I can get it ready by 9/29 for the next 200 yard club match.

LOL No problem is to big to fix some how!

Sorry for your loss. However, I am sure you are relieved to have (maybe) found your load. Good luck, I hope you did.

A side note to the above. I meassured the group just now and it is .694 outside to outside or .386 center to center, if this holds true or even cloose I will be one happy camper.

good to hear! i can't wait forr the overall assessment, hope it works.

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Originally Posted by rjtfroggy

A side note to the above. I meassured the group just now and it is .694 outside to outside or .386 center to center, if this holds true or even cloose I will be one happy camper.

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I am really happy for you RJ, I know you went thru a lot in addition to the .308 accuracy issue. Great to hear you you are in the short rows with the .308 load now.

updated in original post

froggy, I have been following this thread and understand your frustration. From a distance, it seems to me the amount of "jump" built into your ammo could be a probable cause of the erratic grouping. Are you using the Cartridge Overall Length (C.O.A.L.) measurement and comparing your measurement to the SAAMI specification for .308 Win.. In my Nosler, Hornady, and Speer manuals the SAAMI specification for the .308 Win. is 2.810" C.O.A.L. from the base of the brass to the tip of the bullet. This measurement is essentially meaningless for determining the amount of "jump" your bullets make before hitting the lands in the barrel.

You need an OAL gauge and Bullet Comparator such as those made by Hornady and Sinclair and a good caliper to determine the amount of "jump" the bullet makes before hitting the lands. If you do not want to go through the OAL and Comparator gauges (about $50.00), at least load some rounds to the 2.810" SAAMI specification to see how that groups. If those rounds group pretty well, and I believe they will, consider my suggestion below.

My suggestion is that you purchase one each of the above two gauges and, following their instructions, load three rounds each with a "jump" of .025", .020", .015" and .010", using the same brass, bullet, powder, powder charge and primer. Then head to the range and check for grouping. If one "jump" distance provides a better group than the others, you can fine tune that "jump" about .002" shorter or longer for best accuracy.

The above process might also provide some enjoyment, eliminate some frustration, and save you some big $$$$.

Whatever you decide to do, Good Luck!

You say in line six of your original post "... Then I shot the 2.773 which is .002" shorter than Sierra's OAL...". That would mean Sierra's COAL specification is 2.775", or .035" shorter than the SAAMI specification of 2.810". That great a difference seems strange to me. "OAL" to me means the distance from the base of the brass to the ogive of the seated bullet. Perhaps I am confusing C.O.A.L. and O.A.L. as used in this discussion. My apologies if I am incorrect and confusing the discussion.

John I do have the Sinclair tool and have done 99.9% of what you suggest.Over the past 13-14 months I have tried from a light jam to as much as 0.100 jump in 0.003 increments, got to the point where I would not let my meassurements vary by 0.0005 inother words everything as close to exact as possible. Probably why my round count is up to 475-500 and out of all this I have gotten 4-5 groups of under 1".
I have too date taken the gun apart and reassembled at least 5 times,tried different torgue values 2-3 times, changed scopes 4 times,went from a "Rock" front rest to a custom one and have used both old and new front and rear bags, I even tried a different stock twice.
A couple of months ago I was told by a custom gun maker to stop chasing my tail and use the barrel for a survey stake but being stubbern I wouldn't give up, until now. New barrel is on it the way and I will start over. Thanks for your thoughts.

froggy, It certainly seems you have covered all the necessary reloading bases at least a couple of times. You have been tenacious as hell trying to solve this grouping problem. It seems the gods just were not smiling on your efforts. Sorry my suggestions and those of others were not as successful as we had hoped. I imagine you are giddy with excitement anticipating the birth of a new barrel.

This new barrel will shoot 100 yd., ten round groups in one ragged hole. Two hundred yard, ten shot groups a slightly larger one ragged hole. Your tenacity deserves at least that much. Let us know how the new Criterion performs. All who contributed to this thread are curious about the source of the problem.

Best wishes and Good luck!

I sure hope you get a shooter. The Criterion barrel that I have sure is.