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Post by ezekiel38 on Dec 7, 2019 0:02:20 GMT -5
As several of you know, I purchased a "custom" Smith and Wesson .45ACP revolver that the barrel had been cut to 4" and set up for a SD carry gun. Front sight was ground down too low and I ordered a new sight from Midway and installed it. Got the sight whittled down to the proper height but at 20 yards I tried 3 different cast loads and the best was a 5 inch group. ACK!!!
Came home and cleaned the cylinder and dropped a new jacketed .452 slug down all six holes in the cylinder and the aforementioned .452 slug didn't even bother to slow down before it fell out the lower end of the cylinder chambers.
Haven't miked the cylinder mouths yet but I'm going to have to soon! Where do I find oversize slugs to shoot in this monstrosity. Everywhere I have looked it's been 451 to 452. Looks like 454 or 455 will be necessary.
No more Gunbroker deals.
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Post by 45MAN on Dec 7, 2019 7:00:52 GMT -5
I AM NOT PUTTING THIS OUT AS "GOSPEL" BUT JUST AS IMPRESSIONS BASED UPON SOME EXPERIENCE WITH THE SHORT CYLINDERED MODEL 25 45 ACP/AR REVOLVERS AND THE SHORT CYLINDERED 125th 45 COLT, MY IMPRESSION IS THAT THE OVERSIZE THROATS MATTERED LESS WITH THE SHORTER CYLINDERS THAN WITH THE LONGER 25-5 CYLINDERS. I PROBABLY SHUD PULL OUT MY ACCURATE 1955 ACP/AR AND CHECK ITS THROATS, BUT MAYBE THE PROBLEM WITH YOUR REVOLVER LIES SOMEWHERE OTHER THAN ITS CYLINDER? BARREL??
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Post by Ken O'Neill on Dec 7, 2019 7:48:10 GMT -5
I only ever owned one 25-2, (~1978) and will never own another. I don't remember the dimensions of the cylinder throats with certainty at this late date, but they were on the order of .456-.459. Accuracy was impossible, and impact was about 6-9" high at 25 yards, depending upon bullet weight, as well as several inches beyond possible sight correction left. The gun was new.
The American Rifleman ran a story after that, about 30-35 years ago, describing similar throat and accuracy problems that a guy was having with his 25-2. He eventually got sort of satisfied using very large diameter bullets as I recall, and after doing some other things.
The problem isn't Gunbroker, it's the 25-2, which is known for having erratic and large throats. The performance of the couple that I saw in the early days of NRA Hunter's Pistol competitions was very poor.
On the other hand, my 25-5 (45 Colt) was acceptable, and my 3 625's were very good.
I think you MUST measure the throats; it may take .458 bullets (Midway?) that can be resized down. Then again, there's the problem of a .451-452 barrel, and potential high pressures. Measure it, too.
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Post by bradshaw on Dec 7, 2019 8:26:35 GMT -5
ezekiel38.... as 45MAN suggests, the problem may lay elsewhere. Or, more precisely, inaccuracy of your cobbled M-25 may be a combination of infections. Super revolver accuracy requires all major players coming together for the orchestra: bore & groove, forcing cone, chambers, chamber-to-bore alignment. (Muzzle crown cannot begin to rank near the aforementioned unless the crown truly is a wreck.)
Very good accuracy may be obtained from a revolver not quite right. For instance, chamber-to-bore offset may be .007-.008”, even a bit more, but bore & groove are satisfactory, the forcing cone is concentric, smooth, and not oversize, and chamber exits are firm. Add to it this bit of alchemy: some bullets are more forgiving than others.
To show how dangerous a forcing cone can be, put a crooked, rough, excessively deep forcing in an otherwise perfect revolver and see what happens. That gun and a sack of Franklins won’t bring you the top championship.
Watermelon exit holes allow a bullet to tip and hit the forcing cone off-axis. A smooth, low angle forcing cone can help align the bullet to the bore, but damage has been done.
Slug the bore with a lead egg sinker, feel for loose or tight spots. Measure groove diameter. Look at the forcing cone. And you may have to try .454 bullets, possibly powder coated.
Note: Ken posted as I wrote; seeing his take, the suggestion may be to sell to some shopkeeper whose store is about 4-foot wide.
David Bradshaw
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Post by jimtx on Dec 7, 2019 10:49:25 GMT -5
To add, I believe some guys would get a Smith model 26 cylinder they supposedly had tighter thoughts and installed them on the 25-2s.
There is a RB custom 25-2 cut to 2.75” on GB kinda like what I wanted to do to mine in pawn jail currently.
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Post by ezekiel38 on Dec 7, 2019 11:18:10 GMT -5
More measurements to be forthcoming. It is a pinned barrel. If worse comes to worse I may try a caliber conversion. I don't want to dump this old floozy on some unsuspecting gun buyer, I'd rather rebuild it. 41 Magnum 4" could be entertaining.
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Post by bradshaw on Dec 7, 2019 12:46:21 GMT -5
More measurements to be forthcoming. It is a pinned barrel. If worse comes to worse I may try a caliber conversion. I don't want to dump this old floozy on some unsuspecting gun buyer, I'd rather rebuild it. 41 Magnum 4" could be entertaining. ***** Ken O’Neill articulates the chambering ambivalence which plagued manufacturers of .45 Colt revolvers for several generations, if not most of a century. The problem seems to be more than a dimensional transition from .454 black powder bullets to .452 cast and .451 jacketed bullets. By comparison, the German switch from .318 to .323 bullets for the 8x57mm Mauser looks smooth as cream. Smith & Wesson and Ruger tripped over their own feet on how to chamber the .45 Colt. I’ve shot a fearsomely accurate Colt Peacemaker 4-3/4" built in 1897 out to 200 yards with cast .452 255 SWC’s over a 6.7/HP-38 that proves the old manufacturers knew about revolver accuracy going way back. Chamber exits on that old Colt measure .452-inch ! Fortunately, dimensional ambivalence never plagued the great magnum .357, .44, and .41. The magnums didn’t hit the ground running, they hit the ground screaming all the way to yonder target, punching like a fighter on arrival. Us lowly sixgunners were the beneficiaries of proud serious manufacturing. In our lifetime, shooters have had to drag manufacturers of .45 revolvers to the party. David Bradshaw |
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Aggie01
.375 Atomic
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Posts: 1,770
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Post by Aggie01 on Dec 7, 2019 17:14:29 GMT -5
I did a terrific amount of reading/research when I decided to pick up a .45 Colt N frame smith, and both of mine have/will have rechambered cylinders from .41.44 mags. Not just the throats are iffy, but the chambers can be on the big side too.
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Post by magnumwheelman on Dec 7, 2019 17:29:10 GMT -5
Not to put lipstick on a pig, but could the bullet be swagged out to match the cylinder or throats, an some sort of oversized die used, or polish out existing dies???
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Post by rjm52 on Dec 7, 2019 21:21:34 GMT -5
Been dealing with this myself since the 1970s...
Friend had one back in the 70s when we were in college. He was trying to use the original Keith 240 grain AR bullet but didn't get the accuracy he wanted and a lot of barrel leading. I don't recall the mold number but he switched to the 255+- grain with a gas check and things improved a lot...
Bought one in 1978 to carry on duty but before it ever made qualification as it was appropriated by my wife...so I got a .41 instead.. Tried several different loads but the only one that was stellar was one in a SHOOTING TIMES article by Bob M(?). It was a 225 Speer JHP with I believe 6.0 grains of Unique...that was a tack driver...the only one.
I believe there is also a second problem with the depth of the rifling being somewhat shallow so any cast bullet basically has to be made of linotype metal to grab the rifling...
Currently have a 625-7 PC that has a short cylinder and 5.5" barrel...have shot it with jacketed and cast and zero accuracy issues...
Bob
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Post by ezekiel38 on Dec 9, 2019 22:30:57 GMT -5
Yeah I didn't want a project gun but I got one. Slugged the barrel with the egg sinkers and it mikes out at .451. There are qualifications to that statement: I am not a machinist, I'm not even mechanically inclined. The grooves are shallow and narrow in the barrel. Will try some more bullets, jacketed and cast with GC and see what I have. I need someone who is better with a Mic to correctly read out the chamber mouths. I have a neighbor who is an excellent machinist and a farmer. Several Bridgeports in his shop. He's in the process of building a new welding table, I will see if he will take pity on me and measure the mouths. I've measured them and only two are identical in diameter. But I'm a retired cop, not a metal worker. Will keep you posted.
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Post by 45MAN on Dec 10, 2019 6:53:21 GMT -5
JUST ANOTHER "IMPRESSION" FOR OVERSIZED THROATS ON THE SHORT CYLINDERED MODEL 25's, USE WFN's
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Post by z1r on Dec 10, 2019 12:34:47 GMT -5
More measurements to be forthcoming. It is a pinned barrel. If worse comes to worse I may try a caliber conversion. I don't want to dump this old floozy on some unsuspecting gun buyer, I'd rather rebuild it. 41 Magnum 4" could be entertaining. ***** Ken O’Neill articulates the chambering ambivalence which plagued manufacturers of .45 Colt revolvers for several generations, if not most of a century. The problem seems to be more than a dimensional transition from .454 black powder bullets to .452 cast and .451 jacketed bullets. By comparison, the German switch from .318 to .323 bullets for the 8x57mm Mauser looks smooth as cream. Smith & Wesson and Ruger tripped over their own feet on how to chamber the .45 Colt. I’ve shot a fearsomely accurate Colt Peacemaker 4-3/4" built in 1897 out to 200 yards with cast .452 255 SWC’s over a 6.7/HP-38 that proves the old manufacturers knew about revolver accuracy going way back. Chamber exits on that old Colt measure .452-inch ! Fortunately, dimensional ambivalence never plagued the great magnum .357, .44, and .41. The magnums didn’t hit the ground running, they hit the ground screaming all the way to yonder target, punching like a fighter on arrival. Us lowly sixgunners were the beneficiaries of proud serious manufacturing. In our lifetime, shooters have had to drag manufacturers of .45 revolvers to the party. David Bradshaw That being said David, it seems like Ruger may have arrived at the party at long last. I've recently acquired five of the New vaqueros and all have .452" throats and all will shoot when I do my part. That, or I am just very lucky. I'm glad everyone's efforts may have finally paid off.
Now, my Ruger .44 mags have all been very accurate. My 7.5" SBH will routinely take clay pigeons at 75 yds even with me behind the wheel. I was so excited when Ruger introduced the 5.5" version with the rounded trigger guard that I immediately bought one and was glad I did because, despite being a good bit handier than its big brother, it shot every bit as well. That revolver got stolen and a decade later I bought another and was always disappointed. Recently, some many years later, I was introduced to the idea of measuring cylinder throats and low and behold I have a probable cause for the lack of accuracy. Have not gotten around to implementing the fix yet, as the 44 spl and Colt have been getting most of my attention recently. Hope to correct the throats and report back some day.
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Post by rjm52 on Dec 11, 2019 20:44:30 GMT -5
ps...I checked my Load Data book when I got home and it is 7.0 grains of Unique, not 6.0... Velocity from a 6.5" barrel using Remington AR brass was 840 fps...
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Post by ezekiel38 on Dec 13, 2019 0:41:40 GMT -5
Thank you RJM. I'm scouting for 45 bullets now and I remember that bullet from Speer. Experimentation is in the offing. Considering a 240 grain 45 Colt slug at 452 to see if they will stabilize.
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