Need more info on barrel fitting

[krod47nw]

This is my first attempt at fitting a barrel.  I have read the FAQs on barrel fitting, but still need some guidance.  I have 2 barrels to fit to one of my frames.  According to the numbers scribed on them, they both came from the same rifle.  They do not latch, but they have no visible gap at the top.  Should I be looking into filing the pivot, or the fit of the latch?  How can I determine which needs to be done?  Where do I start?

The next question is; the FAQs list the max engagement of the latch at .080", is there a minimum spec? 

[trotterlg]

My personal experience with barrel fitting it that the amount of play in the latching release lever has more to do with the limits of latch engagement than the amount of latch shelf engagement.  .080 may be too much and you will run out of latch travel.  Smoke the breach of the barrel and see where it is hitting the standing breach of the frame, that will tell you what you need to do to make it fit right.  Larry

[quickdtoo]

I've fitted a bunch of barrels, you need to make sure there's minimal gap at the frame, initially, the easiest way to see that is to hold it up to a bright light and look across at the level of the firing pin and above it, usually there will be a slight gap at the top, narrowing towards the bottom. If there's no visible gap and the barrel isn't loose when it's locked up with no forend on it, check the gap with feeler gauge blades to see what kind of gap is actually there, a well fitted factory barrel will be tight on a .001" blade, but not all are that tight, a lot with be snug on .001" and tight on .002". You can check it at the very top and on each side, sometimes they'll be tighter on one side than the other too. Once that gap is as it should be and the barrel locks up tight with absolutely no movement without the forend on, then work on the latch engagement, .080" max, .060" is pretty much ideal and works very well for me. As Larry said, the closer you get to the max, the sooner the latch will reach its maximum travel as the shelf wears and the barrel will be loose.

Another issue that you'll see is the barrel face won't be flat, so you'll see a gap on just part of the area where the barrel meets the  standing breech, this also more than likely means there's too much headspace and should be checked and corrected before fitting the barrel, I explain that in the barrel fitting instructions.

Tim

[krod47nw]

Tim,
When you say to check if the barrel is loose, do you mean side to side movement?  It's hard to check that when it doesn't latch. 

[quickdtoo]

On well over 30 barrels/frames, I've never had one that had no gap at the breech that wouldn't lock up, even if there is a slight gap, the latch should engage the latch shelf, if it won't lock up at all, there has to be a gap at the top of the barrel, or the latch shelf is way too high, one or the other. If the barrel fits the standing breech with absolutely no gap anywhere, then the latch shelf needs to be honed down, assuming the latch is working properly.

When you drop a round in the chamber, is the headstamp face flush with the barrel face or recessed slightly? Any recess is additional headspace if there's any gap at the frame/barrel face. That also needs to be addressed before you do any fitting.

Yours sounds like one that H&R could fit if I understand you correctly, they will for $15 each plus the $10 return shipping, according to MSP's recent post, something to consider.

Tim

[krod47nw]

Tim,
First I want to thank you for responding to my post.  Your input is much appreciated.
New information.  I went back and rechecked.  2 barrels, both marked with the same number.  One is a 24" 223, the other a 30-06.  The 223 has a gap at the top as you suggested. It does not latch.  I don't have a loaded round for the 223 the check the head space.
The 30-06 has no visible gap at all.  I checked it with a loaded round and it has a very slight recess .001 at the most.  Also does not latch.   

[quickdtoo]

Do you know the history of these barrels? If each fits your frame differently, then I would think one or both has been altered at some time since they were originally fitted. Regardless, the .223 barrel needs to be checked for headspace before making changes to the pivot. I'd get some .223 brass or ammo and see how one fits.

The '.06 barrel needs latch shelf work to allow it to lock up, smoke the latch as see where the latch hits the shelf, probably on the very edge.

Tim

[krod47nw]

Tim,
the guy I got them from had purchased them and had them fitted directly from NEF.  He used both on the same frame.  I'll let you know how the latch smoking goes.

Thanks again,
Kevin

[quickdtoo]

The number etched on the underlugs wouldn't be 470 would it? (Finally remembering a previous PM!! )  That's really odd that they would fit a different frame in 2 different ways.

Tim

[quickdtoo]

After a little more brainstorming, the '06 barrel may have been a little loose on the original frame, the underlug could have been set back a little which would account for it fitting better on your frame as far as the underlug to breech face dimensiion. Apparently the latch geometry on the original frame was slightly different since neither will engage on your frame. 

Tim

[krod47nw]

The number etched on the underlugs wouldn't be 470 would it? (Finally remembering a previous PM!! )  That's really odd that they would fit a different frame in 2 different ways.

Tim

Yes it is !!!       Talk to me 

[quickdtoo]

Dunno what else to tell ya, you're on your own at this point.

Tim

[krod47nw]

I mean, how did you know it was 470?  You obviously know something about these barrels that may be important for me to know. 

[MSP Ret]

Is is not so odd that they fit the same frame differently Tim. I also have a couple of barrels that both fit one frame well but only one will fit a second frame as is. This rather odd occurrence has shown up a couple of times now on my guns so I am beginning to just go with it. There may be some gun and frame combinations that are within fitting specs on one frame  whatever they may be, but one of the barrels may be just a bit off on another frame while the second barrel fits it...it happens....<><....

[quickdtoo]

I mean, how did you know it was 470? 

Cuz I bought the frame your barrels were fitted to!!

Tim

[dw06]

Yep he did,and I got the 308 bull barrel  Just fitted it to a frame last week and shot 9 rounds threw it tuesday.Just trying the 150gr accubonds for now and mild loads were right at an inch for 3shot groups.Will try some 150gr hornadys next and play with seating depth.