I have one made in the 50’s that I had for almost 30 years. Great little belly gun and the same type pistol that Jack Ruby used to kill Oswald.
I have one made in the 50’s that I had for almost 30 years. Great little belly gun and the same type pistol that Jack Ruby used to kill Oswald.
I've got one of the Armscor copies, it's a good shooter!
Currently casting and loading: .32 Auto, .380 Auto, .38 Special, 9X19, .357 Magnum, .257 Roberts, 6.5 Creedmoor, .30 WCF, .308 WCF, .45-70.
All steel gun. I had never checked the gap before, so I just did. The largest feeler gauge I could fit was .013". It shoots to the sights with standard pressure 158 and slightly heavier boolits, mine really likes the old Ideal 358-432! I replaced the wood stocks with a Pachmayr compact made for a Colt.
That is a bit "large." Enough so that I would be cautious firing jacketed bullets for fear of sticking one in the barrel. Lubricated lead bullets should be OK, but you can expect significant velocity loss, about 10 fps for each 0.001" larger gap beyond Mean Assembly Tolerance, normally pass 0.004/hold 0.006 for a new gun before proofing. After proofing it is normal for both dimensions to increase 0.001," with end play not to exceed 0.002", which is the difference when measuring with and without rear [head clearance] gage in place.
Max. gap for new a .38 Special build is generally 0.008." Back in the day police contract orders would usually be built to 0.003 pass/0.005 hold. Is recommended practice that when gap exceeds 0.010" that the barrel be set back a thread, existing cylinder end shake be fixed, usually by stretching the crane arbor and refitting, and the gap re-set to new factory normal production specs of pass 0.004"/ hold 0.006"
While it is fairly common to find old black powder-era guns with gaps over 0.012", such as Colt New service, Single-Action Armys and British Webley's, Speer and others in their reload manuals do not recommend that revolvers over 0.012" cylinder gap be fired at all, because they are worried about "bullet-in-bore" malfunctions.
Last edited by Outpost75; 11-23-2017 at 12:37 AM.
The ENEMY is listening.
HE wants to know what YOU know.
Keep it to yourself.
Good morning
The "cylinder gap" info is interesting. Makes one wonder what Colt did with all the rejects ? Surely they would not pass them onto unsuspecting civilians.
This is one that has been with us down here in the Southern confines of Peru for near 15 years. Has a Hip Grip ... But alas is really just a Police Positive Special with the barrel cut back to 1 7/8. But works just as well and cost 3/4 less than what a Cobra might.
Mike in Peru
Last edited by missionary5155; 11-23-2017 at 07:54 PM.
"Come unto Me, all you who labor and are heavy burdened, and I will give you rest." Matthew 11:28
Male Guanaco out in dry lakebed at 10,800 feet south of Arequipa.
Uh-oh, I'd better re measure and proceed from there!
Correct way to check cylinder gap is not to see how thick a gage you can shove in the gap.
The "pass" dimension is the thickness of feeler gage you can insert completely through the barrel-cylinder gap, so that the gage protrudes through the frame window, and the trigger can be cycled DA to rotate the cylinder through a complete revolution without resistance.
The "hold" dimension is the thickness of a gage which causes resistance to cylinder rotation, such that with the gage inserted, the cylinder cannot be cycled through a full revolution by DA trigger pull.
The ENEMY is listening.
HE wants to know what YOU know.
Keep it to yourself.
Thanks for the lesson!
My "pass" reading is .007, .008 starts to drag.
My "hold" reading is .010, .011 won't let the cyl turn completely.
I'm happier now...... At least I know how to measure the gap.
Repeat the measurement again with sized, empty brass in the chambers. It sounds like you are pushing the empty cylinder back when forcing in the 0.010 gage. Up to 0.002 cylinder end play is "acceptable." I expect that your true "hold" dimension with the equivalent of "rear gage" in place is really 0.008" and the extra 0.002 you get checking an empty gun is cylinder end play. In a Colt that the gap will tighten when the hammer is down and the trigger is held back, because of differences in how Colts lock up. Try the "pass" gage in DA and try to pull it out when holding the trigger back and see if the cylinder pinches the gage and then releases it again when you let the trigger rebound. Another check for end play, with and without empty brass substituting for "rear gage".
Last edited by Outpost75; 11-23-2017 at 01:51 PM.
The ENEMY is listening.
HE wants to know what YOU know.
Keep it to yourself.
In so I can find it again, Thanks Outpost.
[The Montana Gianni] Front sight and squeeze
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |