H&R 270 chamber

[Mike in tx]

I have a H&R 270 that is a beauty to look at. I reload for my stepson's Mossberg and those rounds work great. Now the H&R must have the shortest, smallest chamber allowed. It digested factory OK but the Mossberg reloads would not chamber. I need to FL resize each case and it takes them all day long. I figure the shoulder position is shorter than others. I will measure the chamber after shooting tomorrow.

[versifier]

You said they "would not chamber". I need more details, please. How far into the chamber do they go before they stop? (How much of the case head is left protruding from the breech or will the shoulder not even enter the chamber at all?) That will tell you where the problem occurs, then with logic you can figure out the real question: why? Because it feeds and functions in the Mossberg, I am already tending to eliminate the ammo as the issue and like you wanting to focus on the H&R's chamber. And because the H&R runs fine with factory ammo, the issue is a subtle one we might solve using deductive logic and some simple tests.

Minimum spec chamber or just a tad bit short-chambered I agree is most likely. Less likely is an issue with neck diameter/clearance alone. If it's one of those three issues, any break action can be easily cured with a few careful turns of a finish reamer once the exact problem has been properly diagnosed. Minimum neck clearance and short chambering show almost the same diagnostic: the case slides mostly into the chamber without any binding of the case wall, then if the chamber is too short it stops with the case head just barely protruding from the breech (sometimes just a few thou are enough to cause a problem), while if there is a chamber with minimum neck diameter then the case still enters easily but when it stops it remains protruding more from the breech: the length of the neck. I see neck issues more often when I am loading big fat cast bullets into factory chambers, never when loading jacketed, but I mention it because I met a rifle once that I thought for sure was short chambered. It wasn't. The barrel had been set back one turn and it had been rechambered intentionally with a match reamer ground to minimum specs. I didn't notice the telltale gap in the inletting where the barrel reduced in diameter until after. 20/20 hindsight. Luckily a chamber cast told the real story before I rented the reamer and the owner has been happily neck reaming all his cases ever since. A minimum spec chamber is a bit harder to diagnose as a GO gauge works with no problem and tells you nothing, so then the only real choice is a chamber cast.

Measuring and comparing fired (proper term: chamber obturated) cases from both rifles can only tell you so much because the brass springs back, but if there are clear dimensional differences between them where they are found can point you in the right direction. Not definitive, but indicative. Easiest way to know what's really up with it is with headspace gauges, if you or a local smith has a set. Failing that, a Cerrosafe cast will also tell you the real story, but it's a lot easier and faster to play with gauges if you have access to them - they will tell you instantly and definitively.

Or the factory could have been trying to get one more sharpening out of a reamer and the whole chamber is at, near, or even a tad below minimum specs. I know of two Sav99 levers in .300sav like that. One of them really needs an actual SB die, but the owner isn't willing to pay over $200 for a custom one in that oddball chambering and I don't blame him, so I can't load for it and sadly it only gets factory ammo. FL sized cases won't feed or even enter the chamber loaded singly. He's a hunter, not really a shooter, so I get all the brass he empties for the other rifle. The other rifle is owned by my brother and isn't as extreme, but it gags on neck sized cases unless you load them singly and needs FL sizing to feed reliably from the rotary mag. The chamber neck of that rifle has plenty of room for cast bullets, so for me that makes up for the extra work of FL sizing each loading. And he and my nephew don't shoot it more than once or twice a year so the extra labor isn't going to kill me. I don't know enough about lever actions to do more than put sights or sling swivel posts on them, or maybe polish the trigger surfaces, so I'm not even tempted to mess with their chambers myself like I would with a bolt or a break action.

[Mike in tx]

Tom
First, factory ammo works well. Second, the case protrudes approximately 3/16 to 1/4 of in inch. Sorry I did not measure it. I checked all 70 cases in the chamber as I was FL sizing them. They went in the way they should with one exception and I put that one back through the FL die and it worked. While resizing I did bump the shoulder back slightly. I loaded up 10 as I will work a load up at the range tomorrow. I am using a moderate load of 55 grains of IMR 4831 under 140 grain Interlock. The one's I checked fit well. We will know tomorrow morning. I do think that the chamber at the shoulder is short. To bad 308 gauges won't work but I do not have 30-06 gauges has the H&R is the only one in that family.

[Mike in tx]

I will check the cases tomorrow. I have another 50 thatt were shot in the Mossberg to check against.

[Hellrazor]

Sounds like a shoulder issue. But I could be wrong.

[Kirbydoc]

The shoulder and neck are definitely connected. My neck and shoulder are both outta whack and both hurt too. I have found that turning my neck sometimes eases the problem somewhat.:razz:

[Mike in tx]

Report from the range. Because of my back hurting so I only shot the 270 H&R, sighting it in and then 10 shots for group. No problems at all. I have not checked the cases yet but will before the day is done. The best part, 5 shot groups X2. The first one was less than 1/2 inch at 50 yards. 2 shots touched and the other 3 clustered around it. The second group was 1/2 inch at 50 yards. 1/2 inch with 2 shots touching, another 2 shots touching and the 5th shot just below the upper 2 holer. This rifle was one that I was thinking of getting rid of. No more. I will wring it out at the next range session but my back hurt so I had to stop.

[Hellrazor]

The shoulder and neck are definitely connected. My neck and shoulder are both outta whack and both hurt too. I have found that turning my neck sometimes eases the problem somewhat.:razz:

A boot in the assicus might be warranted :)

[Mike in tx]

Tom, I thought I had 308 gauges but I do also have the 30-06 family gauges. The no go fit like a glove. I have several theories but I want to hear what you have to say. Closed on the no go gauge.

[versifier]

You're right Mike, that chamber absolutely can't be short. The NO GO proves that conclusively. Cross that one off the list.

The evidence appears contradictory. So clearly there's something I'm missing, probably something obvious. I'm more likely to be baffled by something simple when I'm looking for a complex solution. (And I've been working on a writing project the last few days and admit I'm more than a bit short on sleep.) What theories are you considering? I bet you've thought a bunch of things I haven't and one of them is probably the answer. ;)

This is where my thoughts are leading me, trying to eliminate one possibility at a time as I think of them until I come up with something that fits all the evidence, and I'm nowhere near there yet, but so far this is what I've thought of:

If the H&R closed on the NO GO, the chamber is too long. That goes on the list of known facts. (GO=OK, NO GO= OShit, FIELD= OF*ck) In theory anyway, the NO GO is right at SAAMI max dimensions including error allowance. It means as a handloader that you'd have to set up one sizer specifically for that rifle and segregate the brass you use in it to avoid case ruptures and/or head separations. Clearly the rifle is accurate enough to be a keeper. If that were the only problem (or if the other issues turn out to be minor ones) then you'd be good to go.....

But things do not add up. There has to be a piece or two of the puzzle still missing as the data is conflicting. If the only problem is the chamber was cut a bit too deep (and it was, as evidenced by the NO GO chambering) then the reloads from the Mossberg with an in-spec chamber should fit into the longer H&R chamber and they do not, so there has to be another problem. If anything, given the NO GO, fired brass from the H&R should be difficult or even impossible to get the bolt closed on the Mossberg. Not the other way around. Why? I do not know, but now I'm really curious to find out. Do you have access to a bore scope to examine the chamber? Have you run the gauges through the Mossberg? (I have a hard time believing it has a problem, but since things don't add up, one must eliminate that possibility since it is the most easily checked. If anything, the reamer that cut its chamber may be a tad larger in diameter than the one used in the H&R, but that is only a guess.) If there were a serious flaw in the H&R chamber, one would think the fired cases would show it clearly, unless the spring-back of the brass is preventing you from seeing it somehow. My next suggestion would be to make chamber casts of BOTH RIFLES, do some comparative measurements, and see what that tells us. Even if it tells us only that the Mossberg chamber is normal, that's still important as it eliminates a whole bunch of possibles. I could be totally wrong, but I'm still thinking there is some problem with the way the H&R chamber was cut and the possibility of it having a min-spec neck diameter has not yet been eliminated.

[Mike in tx]

The min spec neck is what I am thinking right now. I will recheck the gauges but I had a friend with me when I tested it. I am measuring the cases NOW. Length of fired case 2.532.5. Unfired case 2.529.5. Lyman 49th max is 2.540. Shoulder is 1.948 on both the factory ammo and the fired case. The rim dimensions are .4515 for for the unfired and .4516 for the fired cases. Just ahead of the rim on the body the unfired case is .4114 and fired case is .4115 with multiple measurements with a mic. Shoulder mics out at .4215 on the factory case and .4217 on the fired case. The cases measured are R-P head stamp.

The primers are not abnormal to my eye; poor that they may be. They measure out within .0095 below the head for the factory ammo and .007 on the fired case. There are no marks on the case heads.

These are multiple measurements and appear to be within specs. I realize that there is spring back of the case on firing. I rechecked the chamber with the no go gauge and it chambered. I do not have any unsized cases from the Mossberg. I do have some cerro and will do a chamber cast when it cools down and I have the time as I am nosing around for a new job.

Everything contradicts and I am puzzled. I will check with the fellows on Grey Beard. Nothing makes sense at this time. The brass seems to be within specs. The rifle locks up well and does not flop open on shooting.

[Mike in tx]

The folks on Grey Beard think that it is a minimum chamber.

[versifier]

Well, it can't be a minimum chamber if the NO GO went in. That's for certain. Only in math can the inside be bigger than the outside. And your measurements show there is not an issue with the body diameter, at least not an obvious one.

But headspace gauges tell you nothing about the neck. As I said, I have seen minimum neck diameter more than once when trying fatter cast bullets rifles that had no problems with normal diameter jacketed, as well as in the rifle with the match chamber I mentioned. That's why I asked about how far it went in before stopping. I'm assuming the binding is happening at the neck only.

Mind you, it is possible (if unlikely) that the case is binding below the shoulder, but I would think there would be other obvious signs of it. To eliminate that from the possibles list, you could try coloring the top half of a case you know doesn't fit with a dark marker and inserting it very gently until it stops to see if there is any ruboff on the case body, and exactly where it is binding up.

[Mike in tx]

I miswrote, it was minimum neck that I was referring to. I will ask Jim (stepson) if he has any of the ammo left and if so will try what you suggested.

[Mike in tx]

I found some of the rounds loaded for the Mossberg. The shoulder sits 1.976 compared to 1.948 for the cases fired. The case length is 2.555 compared to the fired case of 2.5295. IIRC I only necked sized these cases as that is my habit for cases to be fired in the same rifle. The reason I bring this up is that I took your advice and colored a case. There were scuff marks on the shoulder and not the neck. Conclusion, reloading practice and outsized chambers in both rifles. I will check Jim's rifle and if need be will reset his barrel. Perhaps it will make it shoot better though it shoots 1.5 MOA. Any comments will be appreciated. As a side note I am NOT going to change the Handi at all.

[Mike in tx]

The shoulder for the Mossberg ammo is 1.976 compared to 1.948 for the Handi fired case. The Mossberg case is 2.555 case length compared to 2.5295 for the fired Handi case. This is for clarification.

[versifier]

Both rifles have overlong chambers? Wow, you won't see that very often in anything but a .303Brit or a Moisin. (SMLE's had interchangeable length bolt heads because there was so much variation in them depending on when and where they were made, the Russians didn't seem to care as long as they went bang every time when it was really cold.) But maybe QC in factory rifles has been slipping. So you'll just need a separate FL sizer for each rifle and keep their brass segregated too. Different color plastic ammo boxes for each should help avoid confusion. That's how I keep them straight with mine and my bro's .308's. I've been loading for both of them for over 30yrs with no problems. (In an emergency, I can shoot his NS sized rounds in my Rem788bolt, but he can't chamber mine reliably in his Win88 lever. Not that I would need to, but I was explaining about neck sizing to him and why I do it one day and we got curious and checked it out.)

IIRC, the Mossberg has a barrel nut like Savages (and Sam's Mausers)? That makes things easier to reset headspace. I doubt resetting it will affect its accuracy level, just its brass life, though it may change its POI a bit. But I would take a close look at that crown with a good magnifier and see if it is even and without any burrs, I know from all the milsurps I play with sometimes a twist or two with a crowning tool really tightens up the groups when I can't get the accuracy level I think the rifle is capable of.

Not much you could do to the H&R anyway, treat the brass like a wildcat (by that I mean be careful not to set the shoulder back any more than necessary when FL sizing to minimize stretching and prevent head separations, same as you would with a rimmed or belted case). With an overlong chamber it is, in effect, a wildcat case that uses the same loading data as its parent. I would think you ought to be able to neck size its own brass for it, and if the neck sizer is a collet die you should be able to use it for both rifles (same press & shell holder) without readjusting.

[Mike in tx]

Do you hear from Sam? I miss his advice and information.

[versifier]

Sam can be found on the FaceBook Reload Bench Group. https://www.facebook.com/groups/229625523718210/ An interesting group he and Aaron have put together.