Are Some BP Revolvers Just Not Reasonably Accurate?

[Smokerr]

My basis of feeling for what I want is a 4 inch group at 25 yards. Kind of traditional test distance when I was doing my early pistol shooting and usually if they have any integrity, that is what they test at now as well (I have seen em cheat with shorter distances and it is, if it can't go any better than that its a loss). I saw an uber expensive gussied up 1911 and they were getting 2.5 inches at 25 yards and raving at the accuracy. Hmm, gun magazine, bought off, I expect the lowest cost gun out of the box to do that.

I am going to have to do the discipline thing and just test the ASP NMA at 15 feet and see what the pattern is. Same with the Pietta. I had target out at 45 feet Sunday and the ROA and the 47 Walker out and was getting sub 4 inch groups at that distance.

I tried the Pietta NMA again Sunday and the shots were all over the place, pretty sure a couple hit the target frame 24 inch wide or missed entirely.

Both those guns have the same twist and erratic shooting from both. I have tried .457/.454 and .451 balls (and a round of JD conical).

The ASP I will keep for its sentimental value. The Pietta NMA (target) I may just sell (I have spare cylinders with it). It just does not seem like either one is worth shooting much. Waste of powder and worse caps.

 

[Sam squanch]

Your chambers are too small, maybe. Get them reamed out to the proper size, several guys on this forum may do it for you.

 

[Smokerr]

The chambers on the ASP are tapered.

The Pietta are straight, need to check measurements again. I think the .451 balls shave just a hair of lead.

 

[hawkeye2]

Drive a ball through the bore and then try it in a chamber. If it slips in it's likely OK, if it shaves some lead the chambers are too small (they should be larger than bore size). I often have mine reamed to .456", shoot a .457" ball through a modified forcing cone and the factory bore.

 

[Rat]

Some may be. But some can be very accurate. The chamber size being smaller than the bore will kill accuracy for sure. Wads will sometimes stick to the ball and cause flyers. Sometimes a revolver likes a different or certain powder size, so one has to try 4fg, 3fg, and 2fg. Good luck!!

 

[Smokerr]

Nice group. I would be happy with that for sure.

I am leaning to selling the Pietta. Its not as entertaining or fun to shoot as the 47 Walker and the ROA. No regrets, I think of it as a learning experience.

 

[SDSmlf]

My basis of feeling for what I want is a 4 inch group at 25 yards. Kind of traditional test distance when I was doing my early pistol shooting and usually if they have any integrity, that is what they test at now as well (I have seen em cheat with shorter distances and it is, if it can't go any better than that its a loss). I saw an uber expensive gussied up 1911 and they were getting 2.5 inches at 25 yards and raving at the accuracy. Hmm, gun magazine, bought off, I expect the lowest cost gun out of the box to do that.

I am going to have to do the discipline thing and just test the ASP NMA at 15 feet and see what the pattern is. Same with the Pietta. I had target out at 45 feet Sunday and the ROA and the 47 Walker out and was getting sub 4 inch groups at that distance.

I tried the Pietta NMA again Sunday and the shots were all over the place, pretty sure a couple hit the target frame 24 inch wide or missed entirely.

Both those guns have the same twist and erratic shooting from both. I have tried .457/.454 and .451 balls (and a round of JD conical).

The ASP I will keep for its sentimental value. The Pietta NMA (target) I may just sell (I have spare cylinders with it). It just does not seem like either one is worth shooting much. Waste of powder and worse caps.

What did your cylinder chamber diameters measure at the depth you were seating the balls? Is this diameter at least.001”/.002” larger than the barrel groove diameter? Can make a BIG difference in accuracy.

Here is some something I have posted a previously a few times.

Most recent Pietta 1858s and 1860s I have obtained have .438 bores, with groove diameters at .450”. Multiple cylinders I have measured were in the .444” range, +/-.001. Reaming them to .451-.452” in general, cut group size by more than half. At 25 yards, went from 6-7”, usually caused by one or two unexplained flyers, down to 2-3” or better consistently. Same powder and charge. Same wad and lube. Same caps. Same shooter. Only difference is reamed cylinder chambers.

 

[Nobade]

Not only chamber size but pay attention to the forcing cone and the crown. Just like any modern revolver, all these things need to work together for it to be accurate.

 

[Ed C.]

What did your cylinder chamber diameters measure at the depth you were seating the balls? Is this diameter at least.001”/.002” larger than the barrel groove diameter? Can make a BIG difference in accuracy.

Here is some something I have posted a previously a few times.

Most recent Pietta 1858s and 1860s I have obtained have .438 bores, with groove diameters at .450”. Multiple cylinders I have measured were in the .444” range, +/-.001. Reaming them to .451-.452” in general, cut group size by more than half. At 25 yards, went from 6-7”, usually caused by one or two unexplained flyers, down to 2-3” or better consistently. Same powder and charge. Same wad and lube. Same caps. Same shooter. Only difference is reamed cylinder chambers.

That sounds just like my stainless '58 Pietta target model. I slugged the cylinder with a .454 RB and it measures .446. I then put it in the bore of the gun, placed a light in back of it and I can see light between the ball and the grooves. Shouldn't that be seating in the grooves also? I can't get any kind of good measurement on the groove diameter. I think I'd like to have the cylinder reamed out. I tried to contact Hahn Machine Works but am getting no response. Is he still in business? Are there any other competent gunsmiths with a reasonable turnaround time that do this work? Thanks for any advice.

 

[Bad Karma]

That sounds just like my stainless '58 Pietta target model. I slugged the cylinder with a .454 RB and it measures .446. I then put it in the bore of the gun, placed a light in back of it and I can see light between the ball and the grooves. Shouldn't that be seating in the grooves also? I can't get any kind of good measurement on the groove diameter. I think I'd like to have the cylinder reamed out. I tried to contact Hahn Machine Works but am getting no response. Is he still in business? Are there any other competent gunsmiths with a reasonable turnaround time that do this work? Thanks for any advice.

Most any gunsmith worth his milling machine can do it easily and quickly.

 

[hawkeye2]

As far as I know Charlie Hahn is still in business. He has reamed all the cylinders I have had done and his prices are quite reasonable and his work is excellent. He has also done other work for me including reworking the chamber and throat on my Shilo Sharps.

 

[Bad Karma]

Charlie was very reasonable and had a quick turnaround as well.

 

[M. De Land]

My basis of feeling for what I want is a 4 inch group at 25 yards. Kind of traditional test distance when I was doing my early pistol shooting and usually if they have any integrity, that is what they test at now as well (I have seen em cheat with shorter distances and it is, if it can't go any better than that its a loss). I saw an uber expensive gussied up 1911 and they were getting 2.5 inches at 25 yards and raving at the accuracy. Hmm, gun magazine, bought off, I expect the lowest cost gun out of the box to do that.

I am going to have to do the discipline thing and just test the ASP NMA at 15 feet and see what the pattern is. Same with the Pietta. I had target out at 45 feet Sunday and the ROA and the 47 Walker out and was getting sub 4 inch groups at that distance.

I tried the Pietta NMA again Sunday and the shots were all over the place, pretty sure a couple hit the target frame 24 inch wide or missed entirely.

Both those guns have the same twist and erratic shooting from both. I have tried .457/.454 and .451 balls (and a round of JD conical).

The ASP I will keep for its sentimental value. The Pietta NMA (target) I may just sell (I have spare cylinders with it). It just does not seem like either one is worth shooting much. Waste of powder and worse caps.

I've not yet worked over one that could not be made more accurate than it was. About the only thing that can really be hard to correct is misalignment of chamber and barrel and even that can usually be accuracy improved with reaming, barrel lapping,crowning and forcing cone work.

 

[nkbj]

That sounds just like my stainless '58 Pietta target model. I slugged the cylinder with a .454 RB and it measures .446. I then put it in the bore of the gun, placed a light in back of it and I can see light between the ball and the grooves. Shouldn't that be seating in the grooves also? I can't get any kind of good measurement on the groove diameter. I think I'd like to have the cylinder reamed out. I tried to contact Hahn Machine Works but am getting no response. Is he still in business? Are there any other competent gunsmiths with a reasonable turnaround time that do this work? Thanks for any advice.

He is dealing with chemo.

 

[Smokerr]

Bore on the Pietta slugs out at .454.

Two of the chambers are .445

The question is if its really bad accuracy does tweaking things make it good or just better than it was?

 

[wiscoaster]

My basis of feeling for what I want is a 4 inch group at 25 yards.

That's a pretty ambitious goal for any pistol. I can do it with my .22 LR target pistols, but anything else, without some kind of optical assist and bench rest, is going to miss that mark. My usual training distance for offhand and iron sights with a pistol is 25 feet. And at that distance, four inches is achievable with most pistols, but takes some practice getting the sight picture and hold just right for the particular pistol being shot. On a good day I can hit a 12 in. gong at 25 yds maybe four shots out of six with one of my BP revolvers. And maybe consider myself lucky to hit it at all with one of my single-shot muzzleloader flintlock pistols.

 

[Uncle Miltie]

Most people use too much powder to get the best accuracy at 25 yards.

 

[wiscoaster]

Most people use too much powder to get the best accuracy at 25 yards.

Good point. Many shooters (incriminating self included) mostly just want the fun of a big bang and lots of smoke. But, hey, there's room for everybody to have fun, no?

 

[hawkeye2]

A 4" group at 25 yards shouldn't be too difficult to achieve from a rest. In the N-SSA we shoot revolvers at 25 and 50 yards and you would need a revolver that's capable of quite a bit better than that to be competitive.

A powder charge of 20 grains + or - a little is the most accurate in a .44 at both 25 & 50 yards.

I would recommend you get the chambers reamed, forcing cone reworked and a trigger job, all that assuming the timing is good to go. After all that it's up to you.

 

[Smokerr]

I am using a rest, not what most people work with as its a range rest and my gun box combined into a rest that works for me, a bit odd but its solid.

I will do some freehand as time and caps permit but right now I am trying to get a decent idea of accuracy and what loads if any work to get that.