Max barrel cylinder gap

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Jac43

Bearcat
Joined
Jan 1, 2022
Messages
1
On my new Single Six Bisley 32 H&R I'm able to slide a .009" feeler gage between the barrel and cylinder. I have a hunch its within factory tolerances but at the highest end of acceptable. What say you?
 

Thel

Blackhawk
Joined
Jun 22, 2010
Messages
615
I have a GP at 0.009" too with a b/c gap. Not happy about it but bet tolerance is up to 0.010" as far as the factory is concerned. None of my other Rugers are anywhere near this value.

Since posting did a search and found a thread on another board where an individual claimed he called Ruger and they said acceptable b/c gap was 0.003 - 0.010". I have seem other threads claim Ruger would not state what was acceptable.
 
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Rclark

Hunter
Joined
Jan 1, 2009
Messages
3,266
I've heard/seen in writing the value 0.010" as the high side also... I was just reading in the 'other' ruger forum where 0.012" was mentioned. Anyway, yes, you are on the high side. Velocity may suffer a little, but see how it shoots before making any hard decisions.
 

Chief 101

Hunter
Joined
Feb 14, 2007
Messages
2,069
in the 1980's I had a Dan Wesson revolver and with it came a .006 feeler gauge and at that time that worked for me well. Now I have Many revolvers of which only 3 of them I have measured cylinder gap. One of them is a 1983 SBH with a cylinder gap a tight .0015, I have shot this one very little. Another is a Maximum with the same gap.. it's virtually unused but seems to be the same .0015 as was a few Max's that went down the road after much use with no issues. Then the latest 686 I purchased last fall is the same and it has had much use for a new revolver with a similar cylinder gap. A few ancient Colt SAA revolvers I replaced barrels on were set to .06" and that worked well for them. I would call the .006" gap as a maximum gap for a modern '357 Mag or 44 Mag. just a humble opinion.
 
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Ruger 10/22

Bearcat
Joined
Mar 23, 2022
Messages
47
I had a Dan Wesson 15-2 357 with multiple barrels & .006" was the feeler that came with the revolver
Man, I loved that thing especially with the 2" barrel
I too have always remembered that gap & being it was adjustable was always set correctly

Have three new sets of feeler gauges I just bought for valve adjustments + gunsmithing projects etc.
Need to check the B/C gap on a few revolvers just to see
 

JStacy

Single-Sixer
Joined
May 6, 2016
Messages
493
I had a 454 super red hawk that had a 0.011 BCG sent it back to Ruger and they sent it back with note "within factory specs" I called CSR and questioned the answer and was told the acceptable BCG, at that time, was .003 to .011
 

gunzo

Buckeye
Joined
Sep 8, 2010
Messages
1,549
I had a hard time getting a positive answer from them on the gap max dimension.

Finally, I was told it was .011" for a GP100. 5 or 6 is really good IMO. 8 or 10 not terrible or not really an issue unless you're after high end magnum velocities.

2 or 3 thousandths is great, as long as all the parts of the gun are in alignment with one another. If not, that tight a cyl. gap can cause problems & velocity gain isn't worth it.
 

Dillon Justice

Bearcat
Joined
May 5, 2022
Messages
73
I recently purchased a GP100 5" Davidson. It had a cylinder gap of 11 thousandths. I called Ruger and they said that it was within factory specs. I checked my other Rugers and they are between 4 and 7 thousandths.
 

Biggfoot44

Blackhawk
Joined
Sep 6, 2009
Messages
676
.002 or .003 gap requires all the dimensions to be consistent , and square , at risk of the gap getting fouled and dragging .

.005 is a good goal for mass production revolvers .

The transition between " desirable " and " not as desirable " is subjective , but lets say around .007 to .008 is not uncommon .
But less , for every mfg , there is a gap between " less than desirable " , and " factory wishing to repair or replace under warranty " . Every Mfg , not only Ruger .

Once upon a time , I briefly had another brand large frame .357 Mag , with a .010 plus B/C gap , that would shoot sub 1 inch @ 25yds .

It moved on to a good friend , and he eventually paid to have Bbl set back , because the idea of the gap bugged him .

I don't think I chronograph'ed it while I had it , but the difference between a .005 and
006 would have a significant difference in velocity .

( Yes , it was chronograph'ed afterwards , and he may have before . but due to his untimely passing , can't access his chrono records .)
 

Chief 101

Hunter
Joined
Feb 14, 2007
Messages
2,069
Mine shoots but only when I pull the trigger...err even if somebody else pulls the trigger it will shoot.
 

beginner

Bearcat
Joined
Apr 20, 2018
Messages
16
I have an old vaquero stainless in 44-40 I bought NITB it had .0025” end gap and after sending it back to Ruger to have the throats opened up to .430” from .427” it came back with the same end gap but had to open it up to .004” for black powder. All of my Rugers are under .007”
 

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