Barrel to bushing fit

[ganderman]

What should the clearance be between the barrel and bushing? My bushing ID measures a .500 and the barrel measures .497 -.498 when rotating in my calipers. They just seemed a little sloppy to me compared to when it was new. (about 1,000 rounds ago) Is there a place I can order a new bushing with the proper ID and a little oversized on the outer dimensions so I can fit it to the slide?

Thanks,
ganderman

[Sandman1967]

Are you have any problems with accuracy?
It would also help to know the make of your gun. Not all manufactures build to the same tolerances.

[mitchjoe]

ganderman:

You hear/ see .001 quite a bit, but I wouldn't think after only ~1000-rounds you'd have any appreciable wear...unless the bushing is "soft".

BTW: Is this a .45? Your measurments are roughly a 1/10th below for std. stuff.

mitchjoe

[ganderman]

Sorry guys, its a .38 Super and the make is Colt. Its a Series 80 and I bought it about 2 years ago new. Accuracy is not what I would call "up to par" for a "limited production" $1000 1911.

Mitchjoe, not to sound bad, but I work with solidworks and in a machine shop all day. A round part with a range of .003 sounds like a lot sometimes. Yes, the gun is reliable, (aside from the aforementioned magazine last shot hold opens), but not what I'd call precise or accurate. There is a lot of slide to frame rattle IMOP.

Thanks for your replies,

ganderman

[1911Tuner]

Actually .003 inch is pretty tight for the barrel to bushing clearance in a production gun. I know that in Tool-and-Die Speak, that's a football field, but not for an ordnance-spec 1911. How's the bushing to slide fit?

.38 Super accuracy was once pretty dismal due to the cartridge headspacing on the rim. Newer barrel design headspaced the cartridge on the case mouth, and accuracy was greatly improved.
Check your barrel to see if there's a stop shoulder in the forward part of the
chamber, indicating the redesigned barrel. If you've got one of the older guns that headspaces on the rim, that might be the reason for your accuracy woes.

[stans]

What Tuner said. Headspacing on that tiny semi-rim was a bad idea, I have no clue as to why Colt thought it would work in the early 1900's when machining tolerances were huge compared to today's CNC machining.

[mitchjoe]

ganderman:

If you purchased the pistol NIB a couple of years ago, I'd be pretty sure headspace is off the case mouth & not the semi-rim. I believe Colt made the change sometime in 1989.

Agreed w/ Tuner and Stans. The .001 is referred to as "ideal"...for what though? My guess is pistols on benchrests & selling bushing wrenches. :D I recently did some minor fitting on an EGW bushing for a Sistema that, from the measurements, I knew would take a little work. The end result was somwhere around .001 on both b-b & b-s fit. After about a month I got pretty tired of having to use a bushing wrench (new & one-time experience for me :D ) & swapped it for an Ed Brown "drop-in" part that was ~.002 on the b-s fit & a wee above .003 on the b-b fit. Ran the same 3 different brands of ammo thru from a rest & if accuracy is any worse I sure can't tell.

King's makes one of the only under/ oversize bushings for the smaller O.D .38 Super/ 9mm barrels if you want to have a bushing fit to your pistol. If your pistol has a SS barrel & you want the bushing "hard-fit" I'd recommend the carbon-steel part.

I'm curious about the lack of accuracy; what type shooting will the pistol do? I really like the .38 Super & 9mm 1911's & own more of them than .45's, but like any other if you're chasing tight stuff from a rest, the ammo can be a pretty big deal; different pistols like different ammo. My 9mm Colt Cmdr. shoots unbelievably well w/ WWB 115gr. FMJ (which is great, the stuff is cheap!), but the project I recently put together likes Remington 115gr. FMJ's the best. Either shoots well enough, but they have a definitive preference.

If you haven't yet done so, I'd recommend rounding up a box or two of at least 3-different brands of ammo & lettin' 'em fly.

mitchjoe

[ganderman]

Right now I'm using PMC 130 gr, +P. I usually just buy in quantitys of 1,000 as it is a little cheaper. I don't really know much about other factory loads (that don't cost a fortune). What other bullet weights are there? Are they all +p? Right now the gun shoots about 3" high at 25 yards and groups tend to run around 3-4 inches off the bench. My other Colt in .45 will actually dump 5 rounds into an inch on occasion with Wolf ammo while shooting at the same bench using the same rest. I just was wondering if the slight slop in the b-b and b-s (I haven't measured the b-s yet) was attributing to the current accuracy.

ganderman

[mitchjoe]

ganderman:

Most of the ball ammo for 38 Super is 130gr. All .38 Super brass is stamped w/ +P to help make sure folks don't stuff it any .38ACP pistols. Federal, Winchester & Remington all have factory plinking ammo available. Natchez Shooter Supply has pretty good prices & quantity discounts (www.natchezss.com).

3" or less @ 25yd's is nothing to sneeze at. Pistols that will hold an inch at the same distance are mighty impressive. It is entirely possible a snug bushing will improve accuracy, but I'd also recommend trying a variety of ammo.

mitchjoe

[emiddio]

why not practice non-bench rest shooting instead ? i used to do bench rest with my handguns all the time -- actually leaning against a wall -- and results never made me happy much.

then i got started on shooting off hand -- 2 handed and practicing shooting quickly and at head size targets. i found it more fun and more likely to help me in a real life shooting situation.

they dont do any match bench-rest 1911 shooting i know of.

i also shoot Colt 38Super M1991a1 guns -- and have fitted my 9mm, and 9x23 Colts with 38Super barrrels also. fitted all 3 guns with barrels for all 3 calibers. 95%+ of my shooting now is offhand.

i dont have a ransom rest -- seems like that would be the proper way to test pure accuracy -- and then you would have all the ammo variables to deal with.

as far as inexpensive ammo -- ive been shooting american ammunition, a-merc.com 38super in my guns. i bought it thru a dealer friend for less than $7/box 50; its not +P and probably not reloadable -- but is new and brass.

it makes shooting 38super almost as inexpensive as 9mm; i like it better than 9mm in the 1911 style gun -- though i shoot 9mm in 1991a1 Colts alot too.

i shoot 45acp, 9mm, 38super, 9x23 Win in my various 1991A1 Colts

[bearandoldman]

why not practice non-bench rest shooting instead ? i used to do bench rest with my handguns all the time -- actually leaning against a wall -- and results never made me happy much.

then i got started on shooting off hand -- 2 handed and practicing shooting quickly and at head size targets. i found it more fun and more likely to help me in a real life shooting situation.

Now that is my idea of fun shooting, a head size target at 10 yards is all the accuracy I need, I am sure if I ever have to shoot in a defensive situation I will not have a chance to bench rest the pistol. Tried the bench rest stuff, to me just plain boring, I shoot for fun. Range I frequent has programmable target carriers that edge out and move to a set distance open for 2 seconds of so and then do the same again to a different distance further out or closer in, now that is fun shooting. If it ain't fun I won't do it.

[mitchjoe]

No argument that more fun types of shooting abound. However, most folks I know (sooner or later) want some idea of what ultimate level of accuracy their pistol is capable of. Maybe a few folks can equal a bench or Ransom Rest shooting off-hand, but I haven't met any :D.

mitchjoe

[stans]

PMC is not always known for producing accuracy oriented ammo. American Ammo (AMERC) is often junk and I avoid it at all cost. Steel cased ammo sometimes works in firearms made in the West, but often it will jam as it is made with little attention to bullet and case dimensions (works fine in the larger chambers found on former Soviet block and Chinese made weapons). To get a good handle on the accuracy potential of this 38 Super you will need to either buy some high grade ammo (the premium stuff, not the discount brands) or start reloading.

Oh, and don't mess with reloading any AMERC cases, the brass varies in hardness, thickness, primer pocket diameter, and the flash holes are sometimes well off center.

[1911Tuner]

Listen to stans...Although PMC is pretty good in my .45s it doesn't produce the accuracy that the guns are capable of. I shoot a lot of PMC ball because it's accurate enough to knock down the plates on the machine at my playtime distance...and at 25 yards when I take more time...but it could be better. The brass is very good though.

I wouldn't put A-merc in a worn-out beater that I hated. I even get hot if I happen to find any in my brass that gets mixed in at the range. The stuff is worse than Wolf.

Good ball ammo can be had with Winchester's QA45. It's not the Wally-World
value pack stuff, and it's about 40-50 bucks a case higher than PMC. Federal's ball is also good, but I don't care much for Federal's brass. A little thin in the area just forward of the web. WCC 230 RN Match ammo is top-grade stuff if you can find it, but pretty expensive for general use. As far as I know, nobody loads
.38 Super match-grade ball. Winchester's 125-grain Silvertip in .38 Soup is good, but expensive.

[Unclenick]

Also note what Stans said about the PMC brass being good. I shot through a case of PMC .308 at one of Gunsite's schools and shipped the brass home for reloading. Keep yours, and have someone you know who reloads run it through a tumbler to clean it up and put it in a big zip-lock bag to save until you want to reload.

That aside, all your attention has been on the bushing. As we've all stated in different posts on this forum before, it is fitting the barrel lockup in the slide that carries the lion's share of accuracy improvement in a 1911 pattern gun. By itself, a fitted bushing often makes no distinguishable improvement. Think of tightening the bushing like tuning a piano. Think of tightening barrel lockup like turning off the jet engine next to the piano. You have to do the latter before the former has substantial value.

Nick.

[RickB]

I bought a Colt Super, last Spring, and the bushing fit was "reversed"; it was a tight fit on the barrel, and rocked around in the slide. The accuracy wasn't too bad, with minute of head shot being available at IDPA matches, but that, along with what looked like no crown, caused me to seek the services of my local gunsmithing services provider. He fit a King's bushing, crowned the barrel, and the groups were cut by 1/3. As a sub-caliber trainer for the .45, I love a lightly-loaded Super. I shot a lot of 130-135gr bullets at 1000fps, and the gun is just a joy to shoot.
Other than the funky bushing fit, the gun was well put together. A no-rattle fit of slide/frame, and a decently-crisp 4# trigger. There were some details that I changed to suit me, but it was a solid gun, out of the box.

[ganderman]

Thanks for the replies guys, when I'm done with the last 1,000 rounds of PMC I'll try some different stuff. I'm in N. IL, (Rockford) is there a decent gunsmith you could recommend in my area for some minor fitting?

As for shooting with a two hand hold on the range. 90% of my pistol shooting is not on the bench, just a little bit. If I'm shooting a little high or a little low (or not on the paper at all), then I'll go to the bench to see where the hell its actually shooting. NO, I'm not allowed to "rock and roll" at our range, no rapid fire whatsoever. Shitty............... We had a neighborhood full of $400,000 houses go in right next to our range. Our crack board members decided if we shot as little as possible then they wouldn't try to shut us down. Kinda sucks..........

Thanks for the replies guys............

But what kind of clearance should I leave when fitting the bushing to the barrel?

ganderman