Iffy BC Gap: Should it stay or should it go?

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OK, here's the deal. I have a decent SP101 specimen, except the barrel cylinder gap is a bit iffy.

A 6 mil feeler guage will go all the way through the gap top to bottom.

An 8 mil feeler guage will go almost all the way (95%) through very tightly

A 10 mil feeler guage will go ~1/3 of the way into the gap on the right side

A 12 mil feeler guage will go just a little ways into the gap on the top right side, tightly.

From which I conclude the gap starts out around 12 mills on the top right and finishes out about 7 mills on the bottom left. Pretty consistent across all cylinders.

I know it ain't great, but is it bad enough to send to Ruger for evaluation (they offered to take a look at it if I send it in)?

If I send it in, I would ask them to turn threads off the barrel or replace the barrel to close the gap down to a uniform gap less than 5 mils, whether it was a warranty repair or not, i.e. make it clear I'll pay if I'm asking for better than assembly line "in-spec". I'm not looking for a freebie performance tuning, but I do want a high quality product back if I bother to ship it.

Frankly, I had such a bad previous experience with reject parts being thrown at a warranty return to "fix" it I'm a little gun shy sending it in. I don't want to send it in and get a uniform gap >12 mils across the board to "fix" it, or worse have reject parts like a longer cylinder with oval chambers and bad machining thrown at it.

Should it stay or should it go?
 
What's it doing? If it shoots okay I wouldn't worry about it. I think Ruger will say that is within spec, and any changes will be on your nickel. I seem to remember their max was 0.011", but don't take that to the bank because I am not sure. Only way to know for sure is to call them.
Most accurate Ruger I've owned was a 6" Security Six with a 0.010" BC gap. It was impressive at dusk.
 
I think you are worried over nothing. If it shoots Ok let it go. Go worried about something really broken:)
 
Agreed. It is "in spec." by factory standards. The critical thing is it is not too close that it will cause binding, nor is it at any point outside of the wide limit. The range you describe is common on lots of guns from the factories (unfortunately). Believe it or not, I have seen worse on MUCH more expensive guns they should have used more care on.
 
Terminology?

When you use the term "mil feeler guage" it's not accurate.

B/C gaps are measured in thousandths of an inch, not mils.

One thing to check, are you getting any flame cutting on the top strap?
 
Follow-up: Great Ruger Customer Service

I did eventually get around to sending this one back to Ruger. Asked them to fix if under warranty, or please send me an estimate and I'll pay it; but I would like the gap to be decent.

About 8 weeks later it is back. Barrel replaced, cylinder replaced - both parts as good as original and installed well. Head space remains decent. And gap is uniform, nice and tight on a 6 mil guage. No charge other than cost of shipping to Ruger.

I'm all smiles. Can't wait to put some lead down the barrel. Thanks Ruger!
 
As Roper1952 stated, I think that you mean .006" feeler gage (6 thousandths of an inch), as 6 millimeters would be almost a 1/4 inch.
 
But he didn't say "6 millimeters" (abbreviated mm), he said "6 mil" - and a mil is 1/1,000 inch.

I was wondering about that too... this makes more sense. A 6 millimeter gap would likely cause the bullet to get stuck in the barrel.
 
From a trash bag site; also useful for buying plastic sheeting.

How thick is 2 Mil.

2 Mil. = 50.8 Microns = .0508 Millimeters = 1/500 inch = .002 inches. The standard household Ziploc® sandwich bag is 1.5 Mil. The heavier freezer bags sold in stores are generally 1.75 Mil. 2 Mil. is the standard industrial strength thickness.
 
Thanks for that explanation, DickM, I had never heard of a "mil" before. I learned something new today. :)
 
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