My first test with slugs.
 

I bought a pack of slugs (federal) 12/70.
My gun is a mossberg silver reserve 12/76.

The dude in the shop told me that the 12/76 gun can take both 65,70 and 76 lenght.
I allways acepted this with regular shotgun amunition, but with one single bullet I fear it will hock into the edge in the chamber before entering the barrel if it's not the correct lenght.

I'm not going to risk my health by pulling the trigger and have it all going into my face just because of a idiot in a store not knowing what he talks about.

Is it safe to use slugs in a chamber longer than the cartrige?
My common sence say it won't get guided correctly into the barrel.

Any experts?

Shotgun ammo may used in a chamber LONGER than the shell, but not SHORTER...

So a 3.5" chamber would safely shoot 2 3/4, 3 or 3.5 inch shells, but not vice versa.

Shotgun chambers are tapered..There is no sharp shoulder for a projectile to "catch" on.. You can safely shoot 2 3/4" inch slugs through your 3" chamber, as long as you are not trying to shoot them through a supertight turkey choke or some other choke mot recommended for slugs..

Flippin' metric system... it took me a second to understand what you were talking about.

Anyway, what Pygmy said. So, if you look at your barrel, it'll say the gauge (bore), and the length of the chamber. Something like 12 gauge 3" chamber (or for you metric users, 12 bore 76mm chamber). This means that the chamber is long enough to accommodate 3" (76mm) shells including the extra length when the crimp opens. Essentially the chamber is a cylinder, and for 3" shells the chamber will be about 3.25-3.5" long before the forcing cone. After the chamber comes the forcing cone on barrels that are not back-bored. The Forcing cone is a gradual taper from chamber diameter to bore diameter which smoothly and safely funnels the shot into the bore. If the shell is shorter than the chamber, then there is just a longer "jump" between the shell and the forcing cone, but it is still perfectly safe.

The danger is in using shells LONGER than the chamber. In the case of your shotgun, it would be shooting 3.5" (89mm) shells in your shotgun. Because of the chamber length necessary to accommodate the opened crimp, a 3.5" shell might chamber in a 3" chamber. If this occurs and the gun is fired, the crimp will open against the forcing cone creating a greater than bore diameter constriction of the shot column/slug immediately upon ignition. This creates what is basically a partial bore obstruction, which can cause pressure levels to spike well above the levels the barrel can handle, resulting in the catastrophic failure of the shotgun. To put it in simple terms, you'd be holding onto a hand grenade when it goes boom. Not a great thing for you unless you really like the idea of spending the rest of your life being fed through a straw.

Mike

Driftrider... Very well put...

I worked for over 30 years as an engineering technician for a "high tech" corporation, so the metric/decimal thing is just kinda second nature to me...

I suspect perhaps the original poster is European or perhaps South or Central American..??..

I don't feel so bad. Some of the folks at Nasa don't understand the metric/English system difference either... :s4:

Mike

simply put, there is no need to use any shotgun slugs larger then 2-3/4", all you get with slugs in 3" or 3.5" is felt recoil which in turn hurts trigger pull, which hurts your shooting. Stay with 2-3/4"
Why can't I shoot 2-3/4" slugs through my 3-1/2" chambered slug gun?

A:
Firing a 2-3/4" slug in a 3-1/2" chamber is not recommended because of the length of the jump the slug makes between the end of a 2-3/4" case and the front end of a 3-1/2" chamber. This can cause misalignment of the sabot on the slug, thus causing a serious pressure problem as well as poor accuracy. Slugs are NOT LIKE SHOT SHELLS where a shorter shell can be safely fired in a longer chamber with no ill effects. The bottom line is you should use a shell with a minimum case length of 3" (ideally 3-1/2") in any 3-1/2" chambered rifled barrel for best accuracy. THE CASE LENGTH SHOULD MATCH THE CHAMBER LENGTH WHEN IT COMES TO SLUGS.
Why can't I shoot 2-3/4" slugs through my 3-1/2" chambered slug gun?

A:
Firing a 2-3/4" slug in a 3-1/2" chamber is not recommended because of the length of the jump the slug makes between the end of a 2-3/4" case and the front end of a 3-1/2" chamber. This can cause misalignment of the sabot on the slug, thus causing a serious pressure problem as well as poor accuracy. Slugs are NOT LIKE SHOT SHELLS where a shorter shell can be safely fired in a longer chamber with no ill effects. The bottom line is you should use a shell with a minimum case length of 3" (ideally 3-1/2") in any 3-1/2" chambered rifled barrel for best accuracy. THE CASE LENGTH SHOULD MATCH THE CHAMBER LENGTH WHEN IT COMES TO SLUGS.
Why can't I shoot 2-3/4" slugs through my 3-1/2" chambered slug gun?

A:
Firing a 2-3/4" slug in a 3-1/2" chamber is not recommended because of the length of the jump the slug makes between the end of a 2-3/4" case and the front end of a 3-1/2" chamber. This can cause misalignment of the sabot on the slug, thus causing a serious pressure problem as well as poor accuracy. Slugs are NOT LIKE SHOT SHELLS where a shorter shell can be safely fired in a longer chamber with no ill effects. The bottom line is you should use a shell with a minimum case length of 3" (ideally 3-1/2") in any 3-1/2" chambered rifled barrel for best accuracy. THE CASE LENGTH SHOULD MATCH THE CHAMBER LENGTH WHEN IT COMES TO SLUGS.

First of all, we're talking about a smoothbore shotgun, not a rifled barrel slug gun. The Mossberg Silver Reserve is an O/U shotgun. As such, he'll necessarily be firing either Foster or Brenneke style rifled slugs, not sabot slugs, so there is no issue of having the slug shift in the sabot. Thirdly, the forcing cone on shotguns is very long and the rifled slug is very soft and designed to deform easily to obturate to the bore and then through the constriction of the choke, making the transition into the bore completely safe, especially since the slug will have a good 1/2-3/4" running start at the forcing cone. As for accuracy, nobody's expecting anything great from a rifled slug anyway, so the difference between a 4" group and a 6" group at 100 yards will probably be lost to anyone who chooses to hunt deer with a shotgun traditionally used for upland game.

I know plenty of guys who put half a dozen plus BOXES of 2 3/4" rifled slugs (both Foster and Brenneke style) through 3 and 3.5" chambered smoothbore semi-autos every deer season, usually as fast as they can pull the trigger, and never have any ill effects. If it was dangerous, most of them would be missing a body part or two by now.

Mike

Personally I wouldn't be shooting slugs out of a Mossy Silver Reserve.

I work for NASA; the last time I checked, Kennedy Space Center was still in the U.S.. No metric system here. :biggrin:

Apparently they didn't go over that little detail when they hired the guy that programmed the Mars Climate Orbiter, causing a 125 million dollar "oops"!

Mike