Mossberg 85 - Shell size?

higgscharger · March 9, 2013, 12:06 AM

I recently bought an old MOssberg 85 20 ga bolt action shotgun.

The bolt moves reasonably well for a 70 year old gun, but when i try put a shell through it the bolt will not close all the way.

I pulled the bolt out to try and figure out why. With the bolt out of the gun, i checked the size of the shell in the bolt. Turns out, the brass is larger than the depression on the bolt face around the firing pin. One side of the brass drops in, but the other side sits on top of the rim.

Has the size of a 20 ga shell changed since this was manufactured in the 1930s? Are there particular shells that have a slightly smaller circumfrence that will fit this gun?

OR...

Am i missing something else entirely?

Thanks for the help.

PetahW · March 9, 2013, 09:54 AM

.

Not AFAIK.

Have you inspected the rim recess & extractor hook for a crud build up, and/or tried a different brand shotshell ?

.

BigD_in_FL · March 9, 2013, 04:35 PM

You trying to put a 2.75" in a 2.5" hole?

Virginian · March 9, 2013, 05:39 PM

Unfired shotshells will fit in a chamber that is not designed for them: i.e. a 3" unfired shell will drop right in to a 2-3/4" chamber. But, when fired the crimp will extend past the chamber area and could increase pressures.
I do not know what is going on with the OP's gun. The extractor is spring loaded so it will push shells to one side outside the gun.

higgscharger · March 10, 2013, 07:40 AM

Working off memory, i'll do some careful looking when i get home, but if i recall correctly....

I did check the rim recess pretty well and there was not excessive crud. Not pristine, but nothing to explain this. However, there could be something right at the breech preventing the shell from seating properly in the chamber. I'll have to look more carefully at this.

I tried two brands of shells, i don't recall which they were though. Neither worked.

Is the 85 a 2 1/2 only? I thought it would accept 2 1/2 or 2 3/4?

Regardless, as Virginian said, the shells seem to fit fine, just the bolt won't lock into place. I'll check these things out when i get home and update.

higgscharger · March 10, 2013, 02:01 PM

Alright, a bit more information.

First, this is a Mosssberg Model 85, not an 85A-D.

According to here (which may or may not be accurate, but it is the best I can really find): http://home.epix.net/~damguy/mossber...gun_models.htm

the Model 85 take 2 1/2 and 2 3/4 shells.

Realized that I didn't try two different brands of shells. BOth were winchester, just one was AA Heavy Target Load, one was Super X Lead Shot. So, I'll need to try a different brand.

Going downstairs to clean the bolt face and breech really good, see if that helps.

March 9, 2013, 12:06 AM	#1
higgscharger Member Join Date: February 26, 2013 Posts: 52	Mossberg 85 - Shell size? I recently bought an old MOssberg 85 20 ga bolt action shotgun. The bolt moves reasonably well for a 70 year old gun, but when i try put a shell through it the bolt will not close all the way. I pulled the bolt out to try and figure out why. With the bolt out of the gun, i checked the size of the shell in the bolt. Turns out, the brass is larger than the depression on the bolt face around the firing pin. One side of the brass drops in, but the other side sits on top of the rim. Has the size of a 20 ga shell changed since this was manufactured in the 1930s? Are there particular shells that have a slightly smaller circumfrence that will fit this gun? OR... Am i missing something else entirely? Thanks for the help.

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March 9, 2013, 09:54 AM	#2
PetahW Senior Member Join Date: September 19, 2008 Posts: 4,678	. Not AFAIK. Have you inspected the rim recess & extractor hook for a crud build up, and/or tried a different brand shotshell ? .

March 9, 2013, 04:35 PM	#3
BigD_in_FL Junior member Join Date: December 20, 2012 Location: The "Gunshine State" Posts: 1,981	You trying to put a 2.75" in a 2.5" hole?

March 9, 2013, 05:39 PM	#4
Virginian Senior Member Join Date: February 11, 2012 Location: Williamsburg, Va. Posts: 1,528	Unfired shotshells will fit in a chamber that is not designed for them: i.e. a 3" unfired shell will drop right in to a 2-3/4" chamber. But, when fired the crimp will extend past the chamber area and could increase pressures. I do not know what is going on with the OP's gun. The extractor is spring loaded so it will push shells to one side outside the gun.

March 10, 2013, 07:40 AM	#5
higgscharger Member Join Date: February 26, 2013 Posts: 52	Working off memory, i'll do some careful looking when i get home, but if i recall correctly.... I did check the rim recess pretty well and there was not excessive crud. Not pristine, but nothing to explain this. However, there could be something right at the breech preventing the shell from seating properly in the chamber. I'll have to look more carefully at this. I tried two brands of shells, i don't recall which they were though. Neither worked. Is the 85 a 2 1/2 only? I thought it would accept 2 1/2 or 2 3/4? Regardless, as Virginian said, the shells seem to fit fine, just the bolt won't lock into place. I'll check these things out when i get home and update.

March 10, 2013, 02:01 PM	#6
higgscharger Member Join Date: February 26, 2013 Posts: 52	Alright, a bit more information. First, this is a Mosssberg Model 85, not an 85A-D. According to here (which may or may not be accurate, but it is the best I can really find): http://home.epix.net/~damguy/mossber...gun_models.htm the Model 85 take 2 1/2 and 2 3/4 shells. Realized that I didn't try two different brands of shells. BOth were winchester, just one was AA Heavy Target Load, one was Super X Lead Shot. So, I'll need to try a different brand. Going downstairs to clean the bolt face and breech really good, see if that helps.