Re: JB bore paste diagnoses
Posted: Tue Sep 11, 2018 12:31 pm
I appreciate the thoughts. But I don't think eyeballs are the problem. I last saw the eye doc on 27 April. He knows I'm a shooter and he knows that I need in the way of vision. I'm good to go. And even bad vision doesn't cause 60 YARD misses. Finally, I shot a 24 and then a 30 at BPCR Scope Nationals this year. That's out of 60 shots for score every day. In other words, using a scope did not help. Finally, I did manage to shoot something descent, I don't recall the scores exactly at .22bpcr Irons Nationals. Good enough to take 4th overall and win AAA outright. So, I think I'm safe in saying I can eliminate eyeballs.
As for the rifles. The 2 .45s both have GM barrels chambered with the same reamer and both have won quite a few matches and shot extremely good scores. Good enough to make masters class in BPCR Long and Midrange and Scope and Irons BPCR. So, they have very accomplished track records up 'til recently. Both rifles use the same powder charge as well, but the M77 has a 16 twist barrel (and so is usually used in long range with 537 gr prolate), and the M85 has an 18 twist so it is usually used in midrange and BPCR with a 514 gr bullet. Both bullets are normally 16:1
At BPCR Nationals this year, I shot the 514 gr bullet with 12:1 alloy at least one day (and shot the 24/60 in scope class) and it did not work. Reverting to 16:1 did not help either. I also tried poly wads and fiber wads. The rifle and I have won a lot of stuff with either wad, but neither worked.
This past weekend, I tried a different lot of powder. It failed just as miserably as the previous lot did. So, it ain't the powder.
This past weekend, Jim noted, on Sunday, my 77 and the 537 gr bullets were badly tipped at 1000 yds. Strange since that has not been the case when it shot well. More strange, there was very little wind at the time, so conditions were not radically different than what this rifle has won in, in previous matches. Keeping in mind this has 16 twist barrel I pulled the 537 bullets and replaced with 514 gr bullets (shorter and even more stable). Result: miserable. Bullet stability could not be over come even with super stable twist/bullet length combination. Not surprising since the old bullet shot well in this rifle, it shouldn't matter now and whatever is affecting stability affected both bullets. Given the lack of significant wind during the 1000 yds relay, it's pretty hard to lay the culprit on being too pointy. Pointy won before and will win again, but not with me and these rifles apparently.
What else do we know? Same batch of 5000 primers (BPCR =-2) for the last few years. So that shouldn't be an issue.
Same paper too.
Oh yeah, lets thrown in the muzzleloader (18 twist Bobby Hoyt Barrel with Pope rifling). This rifle shoots the same powder and charge (82 gr Swiss 1.5) as the cartridge guns. It shoots the same 514 gr bullet from the same mould at the highwall, and sometimes it uses the same paper and sometimes it uses an 8# paper. It used to win outright against all others in abut 50% of the matches I shot with it. Early this year, it shot 100-5x at 200 yds and 96ish at 300 yds, but fell apart later in the weekend at 1000. At Harris (all 1000 yds shooting) it was abysmal. It also uses the same 0.06" LDPE wad as the cartridge guns. And it failed with both CCI Mag percussion caps and with the normal RWS - Green Label caps.
Oh yes, this weekend, neither rifle produced the mysterious black gunk that the highwall got at BPCR Nationals this year.
So you are all welcome to throw out your best guesses. Personally, I don't have a clue, but I will gladly listen and critically evaluate any and all suggestions.
Brent
As for the rifles. The 2 .45s both have GM barrels chambered with the same reamer and both have won quite a few matches and shot extremely good scores. Good enough to make masters class in BPCR Long and Midrange and Scope and Irons BPCR. So, they have very accomplished track records up 'til recently. Both rifles use the same powder charge as well, but the M77 has a 16 twist barrel (and so is usually used in long range with 537 gr prolate), and the M85 has an 18 twist so it is usually used in midrange and BPCR with a 514 gr bullet. Both bullets are normally 16:1
At BPCR Nationals this year, I shot the 514 gr bullet with 12:1 alloy at least one day (and shot the 24/60 in scope class) and it did not work. Reverting to 16:1 did not help either. I also tried poly wads and fiber wads. The rifle and I have won a lot of stuff with either wad, but neither worked.
This past weekend, I tried a different lot of powder. It failed just as miserably as the previous lot did. So, it ain't the powder.
This past weekend, Jim noted, on Sunday, my 77 and the 537 gr bullets were badly tipped at 1000 yds. Strange since that has not been the case when it shot well. More strange, there was very little wind at the time, so conditions were not radically different than what this rifle has won in, in previous matches. Keeping in mind this has 16 twist barrel I pulled the 537 bullets and replaced with 514 gr bullets (shorter and even more stable). Result: miserable. Bullet stability could not be over come even with super stable twist/bullet length combination. Not surprising since the old bullet shot well in this rifle, it shouldn't matter now and whatever is affecting stability affected both bullets. Given the lack of significant wind during the 1000 yds relay, it's pretty hard to lay the culprit on being too pointy. Pointy won before and will win again, but not with me and these rifles apparently.
What else do we know? Same batch of 5000 primers (BPCR =-2) for the last few years. So that shouldn't be an issue.
Same paper too.
Oh yeah, lets thrown in the muzzleloader (18 twist Bobby Hoyt Barrel with Pope rifling). This rifle shoots the same powder and charge (82 gr Swiss 1.5) as the cartridge guns. It shoots the same 514 gr bullet from the same mould at the highwall, and sometimes it uses the same paper and sometimes it uses an 8# paper. It used to win outright against all others in abut 50% of the matches I shot with it. Early this year, it shot 100-5x at 200 yds and 96ish at 300 yds, but fell apart later in the weekend at 1000. At Harris (all 1000 yds shooting) it was abysmal. It also uses the same 0.06" LDPE wad as the cartridge guns. And it failed with both CCI Mag percussion caps and with the normal RWS - Green Label caps.
Oh yes, this weekend, neither rifle produced the mysterious black gunk that the highwall got at BPCR Nationals this year.
So you are all welcome to throw out your best guesses. Personally, I don't have a clue, but I will gladly listen and critically evaluate any and all suggestions.
Brent