You should measure the cartridge base to shoulder for all three rifles and compare to SAAMI. Do you have a comparator gauge and threaded case? I would agree, sounds like the Browning is on the high end or out of spec.
The Browning definitely has excessive headspace or at the extreme limit.
My dad had a 270 built on a Mauser action, great shooting rifle, killed lots of game, had a Stith Bearcub 2 1/2 power with a 3 minute Lee dot. Dry weather only due to the fact the scope had an affinity to internal fogging. Started reloading for it, ran into problems after firing the first few rounds, case head separation. Turns out this gunsmith had a habit of building rifles with excess headspace. Essentially only get one firing out of the brass and then chuck it in the scrap bin.
What about the ammo that will only load in the Browning because it happens to have excessive headspace? Doesn't it carry some responsibility in the equation? When multiple rifles work fine with multiple brands of ammo, it would seem more a fault with the ammo when it doesn't load in the same rifles. If an out-of-spec rifle loads out-of-spec ammo, shouldn't they share the blame? In this case, it seems a case of pure coincidence of having a out-of-spec rifle was key in identifying a problem with the ammo. Whatever the case, a learning experience for sure and all the comments and feedback are very much appreciated.
What about the ammo that will only load in the Browning because it happens to have excessive headspace? Doesn't it carry some responsibility in the equation? When multiple rifles work fine with multiple brands of ammo, it would seem more a fault with the ammo when it doesn't load in the same rifles. If an out-of-spec rifle loads out-of-spec ammo, shouldn't they share the blame? In this case, it seems that pure coincidence of having a out-of-spec rifle was key in identifying a problem with the ammo. Whatever the case, a learning experience for sure.
Headspace is defined by the rifle manufacturer when they sized/reamed the chamber. For the ammo, if the manufacturer followed SAAMI specs, it should fit any correctly sized rifle. In general, factory ammo brass is going to be at the minimum dimensions it will ever be so that it can fit any rifle. Rifle manufacturers in general will size the chamber toward the upper end so that it can accept any commercially produced ammo.
If the ammo doesn't chamber, and the rifle's headspace is within SAAMI spec, then the ammo likely has a bullet that is not correctly seated (CBTO) and you are hitting the lands or its case is not correctly sized (CBTS) and the case is hitting the chamber before the bolt can fully close. The only other aspect is the bolt itself is out of spec and/or not matched to the rifle chamber (less likely).
Headspace is defined by the rifle manufacturer when they sized/reamed the chamber. For the ammo, if the manufacturer followed SAAMI specs, it should fit any correctly sized rifle. In general, factory ammo brass is going to be at the minimum dimensions it will ever be so that it can fit any rifle. Rifle manufacturers in general will size the chamber toward the upper end so that it can accept any commercially produced ammo.
If the ammo doesn't chamber, and the rifle's headspace is within SAAMI spec, then the ammo likely has a bullet that is not correctly seated (CBTO) and you are hitting the lands or its case is not correctly sized (CBTS) and the case is hitting the chamber before the bolt can fully close. The only other aspect is the bolt itself is out of spec and/or not matched to the rifle chamber (less likely).
What happens to a cartridge case after firing in a rifle with excessive headspace that keeps it from chambering in another rifle? Based on the comments shared earlier, I'm thinking the pressure causes the case to lengthen slightly at its base due to the excess headspace or gap behind it.
What happens to a cartridge case after firing in a rifle with excessive headspace that keeps it from chambering in another rifle? Based on the comments shared earlier, I'm thinking the pressure causes the case to lengthen slightly at its base due to the excess headspace or gap behind it.
Partially. When a round is fired, the case expands to fill the chamber fully. Basically it is form-fit to that specific rifle chamber. The overall case length grows but mostly that occurs in the region above the case head (base) since the brass is thinner as you go toward the neck. Also, the case expands radially to fill the chamber with the neck region growing the most, again because the brass is thinner and the ID of neck is sized smaller than the OD of the bullet (i.e., neck tension) so that the bullet remains in place until fired. If you have calipers, measure your case at various locations along its length before and after firing the round and you will see how each area changes in dimension. So with different head spacing between rifles, a fired round from one rifle may still fit a second but not vice-versa. When you resize, you do a full case resizing and bump the shoulder back 0.002 - 0.003 inches so that it can easily fit back into the same rifle with a little bit of margin to account for any dust, grit, moisture, carbon, etc in the chamber that might be there. If the head spacing is really excessive, you get a lot of stretching of the brass which can limit the life of the brass for future reloads - you get neck/body cracking from moving the brass a lot and work-hardening of the brass. Annealing can help but generally you only anneal the neck/shoulder region as this is where most of the stretching is going to occur. Hope that helps.
@Alpine01 nailed it, but in a nutshell, the case expands to fit the rifle it was fired in. If said chamber is too long, excessive headspace, it will rechamber in that rifle but not in another rifle that has proper headspace.
Partially. When a round is fired, the case expands to fill the chamber fully. Basically it is form-fit to that specific rifle chamber. The overall case length grows but mostly that occurs in the region above the case head (base) since the brass is thinner as you go toward the neck. Also, the case expands radially to fill the chamber with the neck region growing the most, again because the brass is thinner and the ID of neck is sized smaller than the OD of the bullet (i.e., neck tension) so that the bullet remains in place until fired. If you have calipers, measure your case at various locations along its length before and after firing the round and you will see how each area changes in dimension. So with different head spacing between rifles, a fired round from one rifle may still fit a second but not vice-versa. When you resize, you do a full case resizing and bump the shoulder back 0.002 - 0.003 inches so that it can easily fit back into the same rifle with a little bit of margin to account for any dust, grit, moisture, carbon, etc in the chamber that might be there. If the head spacing is really excessive, you get a lot of stretching of the brass which can limit the life of the brass for future reloads - you get neck/body cracking from moving the brass a lot and work-hardening of the brass. Annealing can help but generally you only anneal the neck/shoulder region as this is where most of the stretching is going to occur. Hope that helps.
