So... here is a short blurb on H&R barrel (*** USE AT YOUR OWN RISK***) fitting...
But first some motivation on possible Swap barrel sets...
Here is the whole .308 family;
.243 & .308;
7mm-08 & .358 Win;
.260 Rem & .338 Fed;
.22 KH & .223 Rem;
.44 Rem Mag & 7.62X39 & .30/30;
.30/30 & .45/70 & 20 Gauge Nickel;
.30/30 & 7.62X39;
.357 Maximum & .44 Mag;
.22 LR Versa & .410;
So, on to barrel fitting;
As I mentioned earlier, approximately half of the barrels made will fit any given receiver (don't hold me to that number, it is based on my experience)... the remaining barrels will require, minor to major fitting, all of which can be accomplished by most anyone.
Barrel fitting will occur at three points;
1. The barrel lug (which engages the hinge pin)
2. The latch shelf (which is engaged by the barrel catch)
3. The barrel to breach face (all fitting here is done to the barrel, not the receiver)
1. The most common issue with a barrel that does not fit properly, is too much play or too little play in the barrel lug. In essence when the barrel lug engages the hinge pin and you close the barrel to engage the receiver, there is too much play and the barrel wiggles around, or the barrel will not close at all. The better of these two problems is if the barrel will not close, which means that material must be removed from the lug pivot surface to allow more room for the barrel to breach face, allowing the barrel to be snapped shut. A word of caution here... go SLOW and check OFTEN. My preferred method is to wrap a drill bit with emery paper (I start with 100 grit), and sand back and forth on the inside of the barrel lug surface, ensuring a straight stroke, do not round off the edges of the lug... eventually, you will get to the place where the barrel will snap closed (you must then ensure proper latch shelf engagement; see below). If you run into a barrel that is too sloppy, you must "build-up" the lug to pivot surface... there are a number of ways this can be accomplished. A quick temporary fix is layer(s) of tin foil on the hinge pin (this is a temporary fix and not a long term solution)... a better method if there is very little build up required is to sand the surface and use JB Weld on the surface, which you then sand down for correct fit (as noted above)... this is better than foiling, however with high pressure rounds this may have to be redone every 200-300 rounds. The best solution is to use "feeler gauge" material to permanently build-up the lug... first burn off the chrome surface on the feeler gauge so that it will adhere. Next, determine what thickness you need, then sand the lug and smear on JB Weld, then place the shim with the proper thickness into the lug and clamp in a drill bit to hold it in place... clamp firmly, and insure that the bit is perfectly perpendicular to the barrel... let dry for 24 hours before using.
2. The latch shelf engagement may be off, generally this is only a problem if the engagement is too shallow (barrel releasing on firing, for example). Generally stoning/filing the latch shelf will correct this issue in short order... again, GO SLOW, and insure that your strokes remain flat to the surface, don't round off the edges. You can "smoke" the shelf to visually check engagement, or use a sharpie marker to do the same... Note... there should be some play (wiggle) in the barrel release button when the latch shelf is properly engaged. If the release button is low and firm, there is probably room for some stoning (some new guns arrive from the factory this way... the situation will correct itself with use/wear, but a touch with a file or stone will fix it in a minute)... it can be disconcerting to have a gun "pop open" at the shot.
3. The barrel to breach surface may require some truing (or squaring). Snap the gun closed and hold it up before a bright light, while looking at the barrel to breach joint/junction from the side... the fit will become apparent. If you cannot see any light at any point in the joint, you are good to go. If there is some light coming through (minimal), but the light stream appears to be equal (parallel or the same) from top to bottom, and the latch engagement is good, the gun will be safe to shoot as is and often will take a set and settle in... I have seen this dozens of times where a parallel light stream disappears after 20-40 rounds. If you find when examining against the light that there is an uneven amount of light streaming through, ie. light only at the top of the junction OR only at the bottom of the junction, then there is room for truing of the barrel to breach face (note again - ONLY work on the barrel, not the receiver). Use a flat metal file, and pay painstaking attention to keeping it flat to the surface, but use more pressure to the side that is contacting the receiver first. IE... if you saw light at the top of the junction, the bottom is contacting the receiver first and that is where you need to remove material... and vice versa, if you see light at the bottom of the junction, then the top of the barrel is contacting first and that is where you need to remove material... NOTE AGAIN... very little needs to be done here... go slow and check often.
In essence those three things will take care of 99% of barrel fitting issues... I have only come across one barrel that was so out of spec that it could not be fit to any of my in house receivers.
