Help understanding 25-5 problem

[brokenprism]

I've read about oversized chamber throats on some 25-5s giving poor accuracy. As I understand it, factory .45 Colt ammo is loaded with .452 bullets, but some Smiths were made with chamber throats anywhere between .454 and .458. Assuming a .452 bullet is fired from a chamber say, .454 wide, wouldn't the forcing cone perform its function of constricting the bullet, and the rifling in the barrel stabilize it? What causes the inaccuracy? As long as the bore isn't oversized, what difference -- within reason -- would the size of the chamber make?

Thanks!

 

[mscampbell2734]

The problem is the oversized cylinder allows the bullet to become slightly cocked to one side so when the bullet does hit the forcing cone its not going directly into the cone but a hair sideways. This in turn distorts the bullet to some degree.

While not a huge issue it DOES affect accuracy to some extent.

 

[jrhoney]

45 Colt ammunition, once upon a time, was loaded with .454 bullets. Older Colt SAA revolvers usually have bores and throats set up for those kinds of loads. But as of late, the move toward a bullet of the same diameter in .45 ACP has left us with two different diameter bullets for the same cartridge through the years.

The only thing I could suggest is to load your own ammo to match the cylinder throats better.

 

[brokenprism]

Thanks, you guys. I didn't realize the angle at which the bullet enters the forcing cone could have such an impact.

I just read a thread on the .41, and while I don't own one, it has persuaded me to to take up reloading. I always seem to get into off-calibers (traded a 25-5 today for a 24-3, same weird ammo situation), and I'm tired of not finding what I want to shoot.

 

[sixpointfive]

I shoot only cast bullets out of mine .454" and it is very accurate

 

[Model19man]

I have found that the Winchester white box 255 gr RNL ammo is very accurate in my 25-5 and 25-2 45 Colt revolvers. You might try some and see if it works as well with yours.

I also load my own with various .454 diameter cast bullets over Unique and find that to work great too.