cylinder throat reaming?

[back40]

I have a blackhawk bisley with .45c and .45 acp cylinders. through plenty of reading it seems almost a rule that the chamber throats are undersized and in need of reaming to provide the best accuracy least amount of leading with lead bullets.

my question is should i attempt this myself, or send it away? the tools cost about $30 more than sending it away, but like the idea of doing it myself, and there's definitely a chance of another ruger single action in .45 in the future. i've read about all on can find on the internet about how to do it, and it seems pretty straight forward. has anyone here done their own, and have any input? while not a machinist and most all of my building and tool experience relating to wood, i am just as mechanically inclined as the next guy.

Also though of perhaps buying the tools to re-cut an 11 degree forcing cone as well, but isn't as immediate and would likely only happen if i were completely unsatisfied with the accuracy after the chamber throats were done.

just for the info i don't currently have the proper way to measure the throats, but with a dial caliper they all seem under the .4525 that they should be.

 

[Varminterror]

For just one or two revolvers, you're better off to just send them in. The reamer and pilots are one thing, but you'll have cutting oil, modified cases, metallic tape, etc into getting equipped to do it yourself.

The 11degree forcing cone reamer kit (including Power bushings) OR paying the smith to do the forcing cone at the same time is often worth it, whether you're shooting lead or not. Ideally, if you get the tools, you should buy the cone gauges to go with it, to help ensure you have the right depth and diameter relative to your throats. The price goes WAY up when you throw in the gauges.

 

[eldon519]

I have done several myself. It is easy. If you mention where you are located, someone might have a reamer you can borrow. I didn't see it on your profile.

 

[joed]

About 12 years ago I bought a S&W 25-5 6" barrel off the S&W forum. The previous owner had the throats done and because of that no one wanted it. Somehow I came to own that gun. I was never impressed with the .45 Colt till I owned that gun, it was easily the most accurate revolver in my safe. Why I ever sold it I don't remember but I wish I still owned it.

 

[454PB]

If it where my gun, I'd find some pin gauges and check the throats first. I own a Ruger BH convertible and the throats are .452".

 

[Walkalong]

Going by my +.0000/-.0002 pin gauges my 25-5 has .456 throats. The .457 won't pass. I bought it used so I don't know if it came that way.

 

[greenmtnguy]

It isn't that hard to do if you are methodical and careful while doing it. Pin gauges are the most accurate method, but it you are a reloader you can use some 45 caliber bullets - either jacketed ones that you measure and find to be as close to .452" as you can, or some larger lead ones. Note I said "bullets" and not loaded ammunition. You can push these through - the jacketed .452 (measure beforehand) should *JUST* slid through with a little effort. Depending on how the lead bullets are sized you might have to push harder to swage them to throat diameter, which you can then measure with your calipers.
Simple 3-in-1 oil can do for cutting oil. To protect the chamber from the cutter/reamer edge, I cut the head off a fired 45 colt case so I could slide it over the reamer - then inserting the reamer from the chamber end and allow the brass case mouth to go up to and stop at the top of the throat where it normally would.
I've done the 45 colt and 45acp cylinders on one ruger bhawk that were undersized ( a 2014 model). My old 1980 bhawk cylinders were actually oversized throats and didnt need the treatment. If you are shooting jacketed bullets and no lead, reaming may not make any difference if you throats are not much under, but with lead it makes a noticeable difference

 

[Vern Humphrey]

I have a blackhawk bisley with .45c and .45 acp cylinders. through plenty of reading it seems almost a rule that the chamber throats are undersized and in need of reaming to provide the best accuracy least amount of leading with lead bullets.

my question is should i attempt this myself, or send it away? the tools cost about $30 more than sending it away, but like the idea of doing it myself, and there's definitely a chance of another ruger single action in .45 in the future. i've read about all on can find on the internet about how to do it, and it seems pretty straight forward. has anyone here done their own, and have any input? while not a machinist and most all of my building and tool experience relating to wood, i am just as mechanically inclined as the next guy.

Also though of perhaps buying the tools to re-cut an 11 degree forcing cone as well, but isn't as immediate and would likely only happen if i were completely unsatisfied with the accuracy after the chamber throats were done.

just for the info i don't currently have the proper way to measure the throats, but with a dial caliper they all seem under the .4525 that they should be.

First of all, how does this revolver shoot? If it ain't broke, don't fix it!

Secondly, if you don't have the means of properly measuring the throats, you shouldn't try reaming them yourselves.

Third, if you do try doing it yourself, resign yourself to buying a new cylinder.

 

[edwardware]

Here's what you're looking for: https://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/59

And a few points from personal experience:
1) If it shoots, don't mess with it (If it ain't broke, don't fix it!).
2) You don't need pin gauges, you need soft lead slugs, a micrometer, and a good set of punches. Measure your throats and bore before you get into this.
3) Instead of reamers, use an appropriately sized steel rod and carbide paper with oil to hone the throats. You still use metallic tape to center the hone, and it goes slower than a reamer.

I did the throats and firelapped an almost new Bisley 45 Colt, and it improved accuracy greatly.

 

[eldon519]

This is what I bought along with the pilot pack. I seem to recall it being cheaper years ago, but who knows. Anyway, I have done several revolvers, and it isn't even remotely hard. Almost seems like it would be hard to screw up.

http://www.brownells.com/gunsmith-t...olver-cylinder-throating-reamer-prod7700.aspx

 

[FROGO207]

I have reamed several revolver cylinders due to smaller than needed throats. I improved the accuracy in ALL of them measurably with lead bullets. The accuracy of jacketed bullets did not change much at all that I could detect. FIRST though you should slug the barrel to see if you actually do even need to ream them or if the reamer you can buy is even the correct size to match the barrel bore diameter. It all comes down to bore size of the barrel and bore size of the cylinder and matching them up well.

 

[texagun]

You need to read this thread. Everything you need to know on cylinder reaming .45 Colts.

http://rugerforum.net/library/18570-forcing-cone-cylinder-throat-chamfering.html

 

[Airman Basic]

Find DougGuy at CastBoolits or the Ruger forum or here https://www.facebook.com/Cylinderhonenet-756429174391912/ and ask him about reaming Rugers. He did several for me and numerous others. Never read a bad review.

 

[ClemY]

Going by my +.0000/-.0002 pin gauges my 25-5 has .456 throats. The .457 won't pass. I bought it used so I don't know if it came that way.

.456" is the old throat diameter for .45 Colt, when .45 Colt was .454" bullets. .456" is the size of my 25-2 in .45 ACP. In .45 ACP oversized throats don't seem to matter much; the primer is so strong in the little ACP case that the bullet clears the chamber throat before the pressure curve of the power charge catches up with it. In .45 Colt it usually makes a very big difference. S&W finally had to resort to replacing the cylinders with .452" cylinders to correct the problem. You might consider calling S&W and see if they still do that.

In the Rugers, as has been mentioned, the first thing to do is try it and see if it is ok or not. If it isn't ok, then you need to measure the throats. 15 yrs. ago I got a couple of .45 Rugers for CAS. The throats were variously .449 to .450 in size, with interesting shapes: S shaped, oval, tapered, etc. Fortunately they were small enough in diameter that the .4525" reamer could clean up the factory mistakes. They benefited greatly from the improvement. I reamed .45 Colt and .45 ACP cylinders. One .45 ACP cylinder was close to .455". I didn't do anything to it; it shot well anyway. One .45 ACP cylinder was a nice, uniform .451". I thought about opening it up to .4525" but it shot so well with .45 ACP MilStd ball that I left it alone. I have had my .45 ACP cylinders trimmed so I can use .45 AR brass in them. I prefer the .45 AR just because it is the way I shoot my 625's and it cycles just a bit smoother than the .45 ACP.

Ruger isn't the only one who produces excessively tight chambers. I used my old DW744 with a 8" heavy barrel for handgun silhouette very successfully. When I stopped shooting silhouette, I replaced the 8" HB with a 6" light barrel. It wouldn't shoot very well. By that time I had a set of pin gages and measured the cylinder. The chambers were very tight, alternating size between tight and very tight. I don't remember the exact numbers now. I reamed it with a .431" reamer. I was afraid it might be too big, but the DW is now the most accurate .44 I have and the throats are still smaller than my Rugers.