JB bore paste diagnoses

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BFD
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Re: JB bore paste diagnoses

Post by BFD » 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

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Lumpy Grits
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Re: JB bore paste diagnoses

Post by Lumpy Grits » Tue Sep 11, 2018 1:27 pm

Brent-With this issue, showing in both of these known cartridge rifles .
Their is but one common factor here.
Have you given any thought to having another 'known' shooter, give these rifles a go?
Respectfully,
Gary
"Hav'n you along, is like loose'n two good men"

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 1:33 pm

Lumpy Grits wrote:Brent-With this issue, showing in both of these known cartridge rifles .
Their is but one common factor here.
Have you given any thought to having another 'known' shooter, give these rifles a go?
Respectfully,
Gary
Love to do that, but where and when is an issue. This is not something I can do at a local range because distances are too limited. No more matches either, but even if there were, who wants to shoot someone else's known lemon at a match?

martinibelgian
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Re: JB bore paste diagnoses

Post by martinibelgian » Tue Sep 11, 2018 2:10 pm

Personally,
When a shooter reaches a certain level, he KNOWS whether he is doing OK or not - you can even determine load accuracy when calling 'pulled' shots - if it's not in the direction called, there is a another issue. Kinda makes me think of my 900-1000 yds performance at Bisley last month. Top score at 900, Barely on paper at 1000...
At any rate, it must be something common to all rifles:
- shooter (but he would know...)
- Alloy - maybe some antimony in the mix, making the alloy harder? Too hard? in both alloys?
- Bullet (but another also failed, so...)
- Paper
- Powder? but another lot also performed miserably...

I know my current lots of Swiss all are seriously lighter for the same volume than previous lots, but I haven't had the opportunity to chrono my loads yet. MAybe a good idea to start out with running shots over the chrono?

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Re: JB bore paste diagnoses

Post by Lumpy Grits » Tue Sep 11, 2018 2:10 pm

Understand- :wink:
Still at this point. This is the only way to eliminate the most common factor of these 2 rifles.
Have you tried any of your other firearms :?:
G.
"Hav'n you along, is like loose'n two good men"

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 2:25 pm

Gert, I'm eyeballing the alloy issue. In the good ol' days, I used virgin lead from the Doe Run smelter and virgin tin from John Walters.

That smelter is out of business so I'm now using new roofing lead scraps. That is, the waste from roofing systems that is left over on a new job - not tear offs. It sure looks pure, if feels pure, it tests pure. But it isn't fresh out of the smelter and hauled to my door directly by a trusted friend like that last 1000 lbs was.

The tin is the same stuff as always.

So, I'm thinking about the lead. The data tells me the bullets are too soft and the noses are slumping - that's why I tried the 12:1, but how could they be too soft? Nothing is softer than my original lead. And even if it was, how could 12:1 fail to fix it?

So I can't logically deduce that alloy is a good candidate - it is, however, nearly my only candidate.

Could it be something I'm doing to my rifles? Either while shooting or otherwise? I have always done long range with 2 damp, one dry patch until this year, when I switched to bore pigs and dry patch. So, last weekend, I switched to 2 damp and 1 dry initially. That failed. I always use bore pigs and dry patch for midrange and silhouette. That remains unchanged. Water has always been my only solvent.

Someone suggested that I slug the bores and look for bulges. I think it is unlikely that I have bulged 3 rifles, but maybe I've done something stupid to all three. I will check for that in the two cartridge rifles. If they show a bulge, I'll do the muzzleloader too.

BTW, inspect of the the crowns under magnification show them all to look excellent.

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 2:28 pm

Lumpy Grits wrote:Understand- :wink:
Still at this point. This is the only way to eliminate the most common factor of these 2 rifles.
Have you tried any of your other firearms :?:
G.

All I can say is that I can hit stuff really well with my .22 and iron sights. The scores at Raton proved that.

I shot the highwall a couple of weeks ago off the bench with a 25x scope @ 200 yds and it shot a 10-shot group of about 3 inches. slightly larger than I would like but not unreasonable. So, I have shot stuff and hit it. But nothing long or even midrange. Only close range or only with a .22.

mdeland
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Re: JB bore paste diagnoses

Post by mdeland » Tue Sep 11, 2018 2:30 pm

I think you need to agitate the bore and break up the glaze!

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 2:33 pm

mdeland wrote:I think you need to agitate the bore and break up the glaze!
Go back to the beginning, read about the brushing and the JB bore paste (the title of this thread). There is no glaze.

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Re: JB bore paste diagnoses

Post by Lumpy Grits » Tue Sep 11, 2018 3:01 pm

Brent-Your comments on the alloy purity is something to look into :!:
FWIW: I get my alloy from John Walters. Have not seen more than 1/2 grn bullet weight variance from order to order.
Let me know if you want his contact info.
Was there any bullet weight or size difference with this mystery alloy, in comparison to your known alloy?
G.
"Hav'n you along, is like loose'n two good men"

VectorMan
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Re: JB bore paste diagnoses

Post by VectorMan » Tue Sep 11, 2018 3:10 pm

Have you changed any of your wiping rods, patches, bore critters, recoil pads, check rest, mat, or any other equipment that might cause a difference in your shooting?
"keep adding powder til it bloodies your nose and blacks your eyes, then back it off bout 5 grains."

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 3:11 pm

Lumpy Grits wrote:Brent-Your comments on the alloy purity is something to look into :!:
FWIW: I get my alloy from John Walters. Have not seen more than 1/2 grn bullet weight variance from order to order.
Let me know if you want his contact info.
Was there any bullet weight or size difference with this mystery alloy, in comparison to your known alloy?
G.

Bullets cast now weigh exactly what they have always weighed when casting 16:1. Nothing new there.

I have not subjected them to hardness testing. Yet.

Vector man. In a word, No.

powderburnt
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Re: JB bore paste diagnoses

Post by powderburnt » Tue Sep 11, 2018 3:23 pm

How many rounds through these barrels? Could they be shot out?

HG

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Re: JB bore paste diagnoses

Post by Lumpy Grits » Tue Sep 11, 2018 3:24 pm

Even if they weigh the same.
Alloy from a different source, may well be worth the try.
G.
"Hav'n you along, is like loose'n two good men"

BFD
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Re: JB bore paste diagnoses

Post by BFD » Tue Sep 11, 2018 3:27 pm

powderburnt wrote:How many rounds through these barrels? Could they be shot out?

HG
Be hard to imagine that happening all at the same time, but here goes best estimates
Highwall - many thousands. How many? Don't know. Less than 10K.,
1877 - half that or even substantially less.
Muzzleloader - hundreds, but not 1000.

Tempting to rebarrel them all but then I'd just ruin those too not knowing the cause here.

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