Cylinder gap surprise SW and Ruger

[Infrequent Shooter]

This weekend I went to the range w a super clean older Model 10 smith wesson. it is tight as can be, it looks like a shooter only, but mechanically it is a 9.9

Also took a fairly new super clean Ruger new model blackhawk. very well cared for. I shot one kind of ammo. 38SP, 148 or 158gr, full WC. both FAs were exceedingly accurate from 7 yards. small groups indeed.

Here is the big surprise. the gas blast from the Ruger was crazy vs the SW, which was completely not apparent. I was very surprised. I dug out a feeler gauge. the Ruger was less than 4/1000, in all cylinders. I did not measure the Smith.

Does this surprise you guys? It was a huge difference in gas escape. It was an indoor range so the blast was very noticeable. The Ruger is very tight and I don't THINK it has any end shake?

 

[mongo chicago]

Definitely check the S&W. I had a couple of S&W's where the cylinder gap was too small and after shooting a few cylinders full the cylinder would heat up and expand enough to begin dragging on the forcing cone and even lock up.

 

[nmkid]

Just yesterday, I watched a video of a guy holding a heavy piece of paper next to the cylinder when he fired off a round. The blast destroyed the paper! Didn't have the slightest idea that it could happen

 

[K22]

I have owned a lot of S&W revolvers over the past 50+ years. Some were used very heavily. End shake is one of the common issues that I encountered as the S&W pistols ages with heavy use.

While some pistol smiths do not advocate using shims to correct this issue, I've used them successfully to restore cylinder / forcing cone clearance within spec. The late Bob Milek was an advocate of using them. That's where I obtained the idea and procedure.

 

[DShortt]

I believe the OP meant the side blast is excessive on the Ruger?

 

[AckleymanII]

.004 gap is OK, I have had some with much more.

You darn sure had better wear safety glasses, and make sure the shooters to your left and right have them also.

Cylinder alignment is a topic that is rarely, if ever, discussed. When the cylinder is out of alignment with the bore, incredible lead cutting occurs, causing material to fly out to the sides. I have a tool to measure the bore alignment with the cylinder; some guns are remarkably out of alignment.

 

[243winxb]

Test fired a Hawes 44 mag western marshal revolver . The cylinder gap was excessive. First shot, i thought the gun blew up.
Nothing like my S&W 29-2 in 44 mag.

Customer had me test fire & check his S&W m27, 357 with Federal factory ammo. Found the ammo to be at fault, as many online had same problem.
Powder was not consumed fully and it blew out small chumks.

 

[243winxb]

If gap is excessive, the barrel can be set back to correct it.

Video link.
Correcting Excess Cylinder Endshake on a S&W Revolver.

There can be high spots on the face of the cylinder. Each cylinders chamber gap needs checked A high spot can be corrected by chucking cylinder in a lathe.

 

[a1712]

Just yesterday, I watched a video of a guy holding a heavy piece of paper next to the cylinder when he fired off a round. The blast destroyed the paper! Didn't have the slightest idea that it could happen

35,000 PSI out of a .004" gap is going to move some air. Brian.

 

[Intheshop]

Look up/into;
Range rod. Be prepared though,these are like a bore scope in that you "may" not like what is discovered.

My last 686,(still less than 500 rounds) came from S$W with a tight .003 gap. It'll tighten to a stoppage by a cpl cylinders of factory ammo. And no,it won't be going back,just haven't gotten round to fixing it yet.

Good luck with your project.

 

[JSH]

Another issue, that will make you shake your head, cylinder throat sizes. Serious about accuracy get a set of pin gauges. You might grin, or you might grumble.

 

[GetReal]

Bill Flippin' Ruger.