So....this happened to me at the shotgun provincials which has never happened with these slugs before.
I've had it happen with some select shells prior (on rare occasion) and was told it was either a problem with the crimp on the shells or the lifter. I've also read it can be a problem with the barrel since there is a sharp edge in there which can cut the crimp a little a jam the shell.
My barrel has been very slightly rounded to get rid of the sharp edge....and this problem was brand new, so I didn't think it had to do with the crimp on the shell. Besides, the S&B low recoil slugs have decent crimp.
After going to the range yesterday and repeating the problem, I suspected in might be a difference in ammo lots (all slugs fired prior to the shotgun provincials were from old stock), the shotgun provincials I used a box from a new case.
This is what I found.
Both boxes of ammo appear identical and are marked at 67.5mm. That said, they are not the same
OLD LOT - 2.29" LOT 1033
NEW LOT - 2.252" LOT 1229
At this point, my working theory is that M2's are hypersensitive to short shells. By slowly cycling ammo through my gun, I was able to reproduce the jam with the short shells, but not at all with the longer shells. I measured AAs and they are roughly the same length as the old slugs....all the AAs cycle fine as well.
This problem has also happened to others with challenger shells from what I've heard. It is commonly blamed on "my gun won't cycle light loads" and now I am starting to think it is more related to shell length.
If anyone has any information to add, please share it. I am going to be testing out different length ammo to see if I am right.
As a side note: after installing a welder lifter, the tip of the lifter needs to be bent downwards slightly to allow cycling. This was already done on my lifter. see Benos for more information on that.
I've had it happen with some select shells prior (on rare occasion) and was told it was either a problem with the crimp on the shells or the lifter. I've also read it can be a problem with the barrel since there is a sharp edge in there which can cut the crimp a little a jam the shell.
My barrel has been very slightly rounded to get rid of the sharp edge....and this problem was brand new, so I didn't think it had to do with the crimp on the shell. Besides, the S&B low recoil slugs have decent crimp.
After going to the range yesterday and repeating the problem, I suspected in might be a difference in ammo lots (all slugs fired prior to the shotgun provincials were from old stock), the shotgun provincials I used a box from a new case.
This is what I found.
Both boxes of ammo appear identical and are marked at 67.5mm. That said, they are not the same
OLD LOT - 2.29" LOT 1033
NEW LOT - 2.252" LOT 1229
At this point, my working theory is that M2's are hypersensitive to short shells. By slowly cycling ammo through my gun, I was able to reproduce the jam with the short shells, but not at all with the longer shells. I measured AAs and they are roughly the same length as the old slugs....all the AAs cycle fine as well.
This problem has also happened to others with challenger shells from what I've heard. It is commonly blamed on "my gun won't cycle light loads" and now I am starting to think it is more related to shell length.
If anyone has any information to add, please share it. I am going to be testing out different length ammo to see if I am right.
As a side note: after installing a welder lifter, the tip of the lifter needs to be bent downwards slightly to allow cycling. This was already done on my lifter. see Benos for more information on that.
