Suggestions Needed On Fire Lapping

[alamogunr]

I have a stainless Bisley in .45 Colt. Initially the throats were .4514(smallest). The barrel slugged .4511, as best I could measure it. It was obvious that the constriction was where the barrel threaded into the frame. I had the throats reamed to .452+. I had originally meant to fire lap the barrel but now am questioning whether that is needed.

My concern is that the boolit will be swaged down in the forcing cone and be a loose fit the rest of the way down the barrel. I plan to shoot it before doing anything more than has been done. Just waiting for warmer weather(Don't laugh, I'm a fair weather shooter).

Any advice?

[truckboss]

Do what you said.Shoot it first you might be surprised.If not surprised then plan b.

[contender1]

Always do one operation at a time & then check to see if there is an improvement. You may not need firelapping. But, if you do, then you will be doing it after your chamber ream, and tests. I have always tried to do one operation at a time to help me diagnose any problems, a it teaches me things.

[largom]

As others have said, one step at a time. With that said, I have always seen an improvement in every gun that I have fire lapped.

Larry

[dubber123]

If I find any constriction at all, I make it go away. I have lapped quite a few, and have never been disappointed in the results. Be prepared for a long lapping session with a stainless Ruger.

[alamogunr]

Tomorrow I'm going to try to slug just the barrel down to where I think the constriction is. Right now, there is only .0016 difference between the throats and the groove measurement of the slug after being pushed all the way through the barrel from the muzzle.

At least one discussion of lapping said to use an unsized boolit. All my .45 molds cast at approx. .454. If my throats are .452+, I'm concerned that the throats will be lapped also. If I lap, I plan to size to .452. That should only touch those points that are less than that. Reasonable??

[dubber123]

If you are confident that the throats are larger than the largest part of the barrel, size to fit reasonably easily through the throats. Remember no lube on the boolits is advised. For what it's worth, I put about 100 well over throat sized boolits through a blued Ruger BH, and as close as I could measure, saw maybe 1/4 thousandths increase in throat size.. That gun went from a 4"+ to an under 2" 50 yd., gun.

[DougGuy]

Lapping loads of .452" would be what you would use. The throats are all within .0002" of each other, and you wouldn't want that to change. If you are under the impression that the barrel beyond the choke is larger, and wouldn't be lapped (as much) because now the boolits are smaller from going through the choke, this is also correct and nothing at all wrong with it. Shoot it, think it over, lap it, repeat until you can't feel a restriction with a tightly patched cleaning jag, then see how much better it gets. Certainly aren't going to hurt it.