Anyone ever swapped BARRELS on Ruger MKI/II/III?

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I put my original upper back on my 22/45 and am getting 2 misfires or more per mag again. So the barrel is at least part of the issue. I won't bore you with the multi-year saga but trust me; I've tried everything I or anyone else can think of.

So now I'm wondering about swapping a replacement barrel into the OEM receiver. Anyone done it? I'd like a long heavy taper or govt profile or even a 10" if I can find one.
 
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I have never done one but from what I have heard it's a big job. Supposedly Ruger installs their barrels on blank receivers then machines the openings in the receiver and the feed ramp. Getting the feed ramp correct on a rebarrel would be a very big job. The barrels are probably very tight in the receivers also.
 
Yeah I've been reading up and it sounds like a pain. The feed ramp is part of the barrel though so timing would be the main problem other than it being too snug to R/R without ruining the receiver.
 
I.. am getting 2 misfires or more per mag again. So the barrel is at least part of the issue.

The barrel face is flat around the chamber on a Ruger, so I have found it not likely at all that it would have anything to do with a misfire. More likely a too deep bolt face recess, short firing pin, or both. How did you determine that the barrel is at fault? Not saying that you are wrong. If you have found some other explanation I would like to hear it as I am always looking to learn something new.

What bolt are you using? Depth of the bolt face recess within spec? Firing pin protrusion correct? What does the firing pin tip look like? If either or both of those are marginal then misfires can occur. Does a round easily seat completely flat against the barrel face or do you have to press it in? Chamber rough or damaged? A chamber iron can be used to carefully correct small irregularities in the chamber. Blueprinting the bolt is a fairly simple process. You can do it yourself or send it to any one of several good Ruger smiths who can do it for a reasonable sum.

Re-barreling one of them is a huge pain. The shoulder torque is off the charts. The barrels can be removed, but it requires a really good barrel vise and action wrench. And there is still a risk or twisting the receiver. If the old barrel is to be sacrificed then cutting a relief notch just off the receiver face to relieve the torque before turning out the barrel will reduce the risk to the receiver. Accounting for feed ramp alignment can be handled by relieving the torque face on the barrel a few thousandths. There's zero reason to torque the barrel factory tight. I don't torque centerfire bolt gun barrels over 100 ft pounds. That's more than plenty for a .22.
 
I have a Mk II that is use with the original barrel and a MKIII barrel, both Ruger factory barrels, both run fine.
 
The barrel face is flat around the chamber on a Ruger, so I have found it not likely at all that it would have anything to do with a misfire. More likely a too deep bolt face recess, short firing pin, or both. How did you determine that the barrel is at fault? Not saying that you are wrong. If you have found some other explanation I would like to hear it as I am always looking to learn something new.

What bolt are you using? Depth of the bolt face recess within spec? Firing pin protrusion correct? What does the firing pin tip look like? If either or both of those are marginal then misfires can occur. Does a round easily seat completely flat against the barrel face or do you have to press it in? Chamber rough or damaged? A chamber iron can be used to carefully correct small irregularities in the chamber. Blueprinting the bolt is a fairly simple process. You can do it yourself or send it to any one of several good Ruger smiths who can do it for a reasonable sum.

Re-barreling one of them is a huge pain. The shoulder torque is off the charts. The barrels can be removed, but it requires a really good barrel vise and action wrench. And there is still a risk or twisting the receiver. If the old barrel is to be sacrificed then cutting a relief notch just off the receiver face to relieve the torque before turning out the barrel will reduce the risk to the receiver. Accounting for feed ramp alignment can be handled by relieving the torque face on the barrel a few thousandths. There's zero reason to torque the barrel factory tight. I don't torque centerfire bolt gun barrels over 100 ft pounds. That's more than plenty for a .22.
what is spec for bolt face recess? OEM bolt, works in new barrel. Have measured and or replaced everything else
 
what is spec for bolt face recess?
Headspace dimension is .043"-.050". I set most of mine at .043"-.044". Also note that rim thickness can vary among certain brands/lots of ammo. You might be running into a combination of thin rims, a bolt at/near max headspace, and a short-ish but still within spec firing pin. Cutting the bolt nose to reduce the rim recess depth gives you a chance to square the bolt face (they often are not) while reducing headspace to a better number and increase the firing pin reach in one fell swoop.
 
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Headspace dimension is .043"-.050". I set most of mine at .043"-.044". Also note that rim thickness can vary among certain brands/lots of ammo. You might be running into a combination of thin rims, a bolt at/near max headspace, and a short-ish but still within spec firing pin. Cutting the bolt nose to reduce the rim recess depth gives you a chance to square the bolt face (they often are not) while reducing headspace to a better number and increase the firing pin reach in one fell swoop.
Mine measures .046"-.048" depending on which lugs you use
 
Well the longest one will determine the headspace. You won't loose anything by bringing it down to .043"-.044". Some folks who are really serious go as low as .041", but I would not unless it was a dedicated match pistol with selected ammo. How far does your firing pin come out of the breech face? Have you scrupulously cleaned the chamber? Is the factory loaded chamber indicator installed? If all else fails a trip back to Ruger may be in order.
 
LCI is gone, mag safety is gone. Have cleaned several times. Frame is modified with 1911 grip panels and bushings plus it has a Clark bushing pressed into the hammer so factory is out. I've tried a replacement OEM firing pin, a "new type" OEM firing pin, a sharpened OEM firing pin, and a VQ firing pin. Have tried swapping bolts. Nothing fixes it
 
Here is a very simple and accurate method to use to measure .22 rimfire rim thickness. Start out with a fired .22 centerfire cartridge case. Measure the cases over-all length:
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Then zero out your calipers at that length.
A .22 rimfire round will slip into the neck perfectly:
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Now measure the over-all length with the .22 rimfire round inserted:
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You now have the rim thickness.
 
Got 3 hangfires, two "soft" rounds, and a squib in one mag of automatch. Swapped uppers, same bolt, same frame, same ammo, same batch= 60 rounds no issues.

this is driving me maaaaaaaaaaaaaaaaaaaaaaaaaad.....
 
I had one some years back that would shave lead off the bullet during feeding. The lead shavings would occasionally keep the bolt from closing 100% and misfires would result.
 
I would suggest talking to Ruger about the issue. If you take any material off the bolt face they won't do any warranty work. Even if they charge to work on it you will have peace of mind. Just my $0.02
 
Called them a while back. They said they have zero MKIII barrels or parts. Not sure I believe it but that's what they said. And since the lower has been modified I'm SOL on warranty work.
 
Thanks for the details. However as noted above: "I've tried a replacement OEM firing pin, a "new type" OEM firing pin, a sharpened OEM firing pin, and a VQ firing pin. Have tried swapping bolts. Nothing fixes it"
 
Thanks for the details. However as noted above: "I've tried a replacement OEM firing pin, a "new type" OEM firing pin, a sharpened OEM firing pin, and a VQ firing pin. Have tried swapping bolts. Nothing fixes it"

I did not scroll down far enough to notice that you had tried a firing pin, so I deleted my post. My experience with firing pins is of no value. I can only suggest looking at firing pin protrusion. Case head dents are not that useful.

I think the best plan is to call Ruger, tell them that the pistol is misfiring, and send it off. I am serious about this, I did this with a Ruger #1 in which the firing pin indentation was off center and the rifle misfired frequently. I talked to the Gunsmith, he had measured the offset, measured firing pin energy with coppers, firing pin protrusion, so I was quite impressed with his investigation. Take out the aftermarket parts, Ruger will toss them out and not return them.

And, call when they get it, and talk to the gunsmith. You might learn something. I did. :)
 
I did not scroll down far enough to notice that you had tried a firing pin, so I deleted my post. My experience with firing pins is of no value. I can only suggest looking at firing pin protrusion. Case head dents are not that useful.

I think the best plan is to call Ruger, tell them that the pistol is misfiring, and send it off. I am serious about this, I did this with a Ruger #1 in which the firing pin indentation was off center and the rifle misfired frequently. I talked to the Gunsmith, he had measured the offset, measured firing pin energy with coppers, firing pin protrusion, so I was quite impressed with his investigation. Take out the aftermarket parts, Ruger will toss them out and not return them.

And, call when they get it, and talk to the gunsmith. You might learn something. I did. :)
Sorry you deleted your post; it may have been valuable to others. The frame has been milled and 1911 grip bushings installed, and there's a Clark bushing in the hammer that is never coming out without being drilled out, and there's a custom extension permanently screwed into the mag release so unfortunately Ruger service is off the table.
 
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