Shotgun 2. 3/4' vs 3'

[rookhawk]

I don't believe anyone has moved off on a tangent. The OP showed a photo of a 70mm Brenneke style slug and questioned was it (along with the other pictured shells) safe to shoot in a 2 3/4 inch chambered shotgun. Typing slowly - Yes they are. Someone else began a dialogue about slugs and full-choked guns - The slug he showed a picture of is a 70 mm Brenneke style that is perfectly safe to shoot in a 2 3/4 inch gun - full choke or otherwise.

He has followed that initial post with a second that shows he is still hung up on mm's and fired casing length. Those two posts have been his sole contribution. Any tangents have been provided by those responding.

Back to the OP. I am repeating myself, but regardless of shot size, load, etc, assuming your shotgun is a modern gun in good shape, I repeat - Your 2 3/4 inch or 70 mm chambered shotgun will handle any load designed for a 2 3/4 inch or 70 mm gun. The box of shells and the shell itself will be clearly marked. The answers are not in the least conflicting. Throw away the ruler. This is pretty simple.

But I will move on. Everyone has answered the base question consistently and accurately.

I understand, @Red Leg . I'm just asking the OP to come back on and ask "the real question". I think there is more to his inquiry. He's working on a "solution" to some "problem" or "need" he has in his head. He hasn't stated what he is really thinking. Beyond staving off a physical injury, I don't think the OP is equipped to move forward solving his problem, he just learned that 2-3/4" marked shells fit in 2-3/4" marked chambers thus far.

I'm encouraging him to lay out what he is trying to do. Does he want to hunt with slugs? What continent/nation? Does he want something accurate, or something that will work at 30 yards? Does he need a gun that will let him shoot 30 yards with slugs and also hunt birds with shot, or is this a purpose-built solution he's trying to figure out for large game?

Sometimes answering a new person's question directly can be unhelpful, because the assumptions that lead to the question may be faulty.

 

[Forrest Halley]

69 or 70mm are 2¾" shells.
76mm are 3" shells.
89mm are 3½" shells.
Have a wonderful day and stop staring at the shells and start emptying them...

 

[BigJohnx13]

Hi all. Thanks for all the feedback. I get the message loud and clear. The rounds that is in my picture will fire safely in a 2 ¾ “ shotgun.

Some background info. I was actively competing in 3 gun shoots a while back in the military. When I purchase my first pump action shotgun the instructor, gunsmith and salesman states that my AAA sponsored rounds (green one in picture) must be fired in a 3” chamber. It was explained in detail about chamber length, forcing cone and round length and why the longer AAA round need a 3” chamber. A 65 mm round + opening is for a 2 ¾” and a 70 mm round + opening is a 3” round. This was my education and info I had to work with when starting and dealing with a shotgun.

This shotgun was my sport competition rifle, my “after hours keep the passage clear” gun and occasional bird hunting gun. The same as my pistol and rifle, one all rounder gun with a few other applications that work well for me. A few years back I had a back operation that impaired my mobility and I stopped shooting competitions. Recently I had a shoulder operation and an upper arm muscle problem that makes cycling a pump action shotgun awkward. For that reason I sold my pump action shotgun and is currently looking for a semi auto for static range shooting, occasional bird hunting and pig hunting. Not planning to shoot further than 50 m (heavy dense bush) with slugs, I still have a fair amount of ammo and would like the new gun to shoot all the available ammo in my possession.

When looking for another shotgun another gunsmith states exactly the opposite of my first encounter with a gunsmith when I request a 3“ chamber gun. When I asked the question about 2 ¾ “ " vs 3"on a English forum almost all states also 3” chamber. See the attached picture. Now understand why I”m confused
pic

Reading up on the internet its seems that I was misinformed by other “misinformed specialist” but many still operate on the idea of physical round length. Hence my questions related to physical round length.

Now you guys must understood why I am confused. My first reply on this forum here is “
3" chamber for all of those” (sorry Hog patrol). I eventually grab all my ammo boxes and scrutinised them.
pic

This is the only markings on the all the boxes whether AAA, no 7 or no 3 rounds. No chamber info, round length info etc. No other info stamped anywhere indicate for which gun this ammo is. So I grabbed my Slug boxes and scrutinized all.
pic

Still no further info. Eventually by chance I turned the box upside down to throw it in the rubbish bin. Low and behold. On the bottom of the box I found this

So it boils down to RTFM. Thanks again for all replies and is now a much wiser and more informed shooter.

PS. If other shooters ask a strange question, remember they could also have been misinformed from day one.

 

[IvW]

Send me all the Brenneke 70mm for my sxs poorman's double 2 3/4" I am running low and fear I will have to have a mold made.....

 

[Hoss Delgado]

Send me all the Brenneke 70mm for my sxs poorman's double 2 3/4" I am running low and fear I will have to have a mold made.....

Did Brenekke discontinue their slugs ?!

 

[Hoss Delgado]

3 inch shells in a 2 3/4 inch gun is only for a person with a death wish .
Not all guns are built to fire slugs , even if they are cylinder bore and have the same chamber length. As an example , l will reference two British Shotgun Makers :
John Dickson and Son of Edinburgh and
W W Greener ( who sadly isn't making Guns anymore ).
John Dickson's employees flatly told me that their guns aren't capable of Firing any shot size larger than #5 bird shot , as the round action isn't strong enough.
Graham Greener of W W Greener told me that none of his guns with ANY degree of choke in them are suitable for firing slugs . It's not really something British gunmakers shine at.
Continental gun makers are more often than not , likely to build their guns capable of Firing slugs. An example is this BRNO over under 12 gauge shotgun which l got recently which is very accurate up to 27 yards with Brenekke and Foster slugs. In a semi auto with a 2 3/4 inch chamber , 2 3/4 inch slugs will work through the fixed choke.
Also , remember that numerical length should not be taken in the literal sense Many of the old Fox Brand 12 gauge side by Side Shotguns were marked " 2 3/4 inch " Chambers , but actually had 2 5/8 inch chambers.

 

[IvW]

Did Brenekke discontinue their slugs ?!

No

Nobody seems to import them to RSA anymore....

 

[Hoss Delgado]

No

Nobody seems to import them to RSA anymore....

If you're based in Botswana , you can have 3 boxes of mine in 2020 during my Mixed Bag hunt. I have acquired 120 slugs over the years ( Fosters AND Brenekke ). All you have to do , is find me a guy who will sell me an 11.2 × 72 Schuler rifle

 

[flatwater bill]

This IS a little tangential, but most 2 3/4 inch 12 ga shells are a bit less that 2 1/4 before firing. 3" shells are near spot on 2 1/2 inches before firing. Kinda useful to know when the writing rubs off of plastic shells.............FWB

 

[rookhawk]

This IS a little tangential, but most 2 3/4 inch 12 ga shells are a bit less that 2 1/4 before firing. 3" shells are near spot on 2 1/2 inches before firing. Kinda useful to know when the writing rubs off of plastic shells.............FWB

But you can have a 3” magnum shell at 13000psi that is only 2-5/8” long when fired. You cannot rely on shell length using a tape measure. Nor can you trust a 2-3/4” black powder gun to shoot a modern 2-3/4” shell either. (Service pressure was the 2-1/2” pressure in a longer shell)

bottom line, if you don’t know a great deal about shotguns, beware. A tape measure or chamber gauge absent knowledge of the gun’s true condition and proof marks is a recipe for danger.

I own thousands of dollars in tools to determine what a shotgun ought to shoot and a tape measure isn’t one of those tools!

 

[flatwater bill]

Most people will not buy "thousands of dollars in tools" before they go duck hunting. They will simply buy the correct ammo. The lengths as stated above are correct. You may be reading way too much into the post.........way up river here..................FWB

 

[flatwater bill]

And BTW................that was not the free Harbor Frt tape measure used above.....that was the $3.99 one with the rolled edges. So I hear ya on the tools......FWB

 

[rookhawk]

Most people will not buy "thousands of dollars in tools" before they go duck hunting. They will simply buy the correct ammo. The lengths as stated above are correct. You may be reading way too much into the post.........way up river here..................FWB

and those people may die from ignorance. Shoving the wrong load in a gun doesn’t end well usually. And for fine guns, they don’t have barrel nomenclature to rely upon, so you better know how to read proof marks, have the gauges to ensure it’s still “in proof”, and put the right bits together.

if modern, just read the barrel and read the shell box correctly. But don’t use a tape measure to think you can measure shotgun shells and decipher what it actually is if unmarked, or if a vintage gun can use that shell.

 

[Ray B]

The main thing I recall as a difference between 2 3/4 1 1/8oz & 3" 1 1/4oz 20 ga Super X Magnum shells was that the recoil in my superposed was more noticeable with the shorter shells. I attributed this to the lesser amount of wadding space.

 

[Red Leg]

The main thing I recall as a difference between 2 3/4 1 1/8oz & 3" 1 1/4oz 20 ga Super X Magnum shells was that the recoil in my superposed was more noticeable with the shorter shells. I attributed this to the lesser amount of wadding space.

2 3/4” shells are loaded standard as both 1 1/8 ounce and 1 1/4 ounce - the Super-X load in 1 1/4 ounces is a 2 3/4 (70mm) load. A 3” shell in 12 bore is normally 1 3/8 to 1 3/4 ounces. Those shells do indeed generate significant recoil. Steel shot (worthless garbage) is loaded as 1 1/4 ounces in a 3” shell.

 

[Ray B]

I was referring to 20 ga shells of which, at the time (40 years ago) Winchester had 3 variations in the SuperX line. Standard HiBase 1 oz, short magnum 1 1/8oz and Magnum 3" 1 1/4oz. the shot was lead (of course, the antis hadn't corrupted the issue at that time).

 

[Red Leg]

I was referring to 20 ga shells of which, at the time (40 years ago) Winchester had 3 variations in the SuperX line. Standard HiBase 1 oz, short magnum 1 1/8oz and Magnum 3" 1 1/4oz. the shot was lead (of course, the antis hadn't corrupted the issue at that time).

Got it. You are correct. A 3" 20 bore shell from the typical 20 bore generates both recoil and and violent speed of recoil. They will help anyone work on a flinch.

 

[Forrest Halley]

Somewhere I have American Eagle #8 plated 2¾". These shells came 20 to a box. They are the hardest recoiling 20 gauge I have ever fired. I used to shoot them for Clays as a kid. I hated them. As an adult I fired some again through the same gun I used as a kid. It was very reminiscent of a .375. Maybe not as bad, but very motivated indeed.

 

[rookhawk]

Just a bit of trivia for the folks here that may explain the recoil gotchas.

The difference between the weight of a 1-ounce shotgun load and a 1-1/8 ounce shotgun load is only 12.5%. However, the latter increases recoil by 50%.

People obsess over that little extra bit of load when it actually introduces more likelihood of a flinch, much more wear and tear on the gun, more pellet deformation and shot string, and no additional killing power. (e.g. it doesn't make the pellets fly faster or penetrate deeper, the additional recoil merely is getting the additional 12.5% pellets by weight out the barrel at the same speed!)

Without exaggeration, I've killed at least 10,000 game birds in my lifetime with loads of 7/8 once and 1 ounce in only 2.5" shells at 1150fps. They are completely sufficient at all wingshooting distances you would consider. No net improvement for hunting with more powerful upland loads. You just don't need more than a square load if shooting shot. With slugs on the other hand, the max misery your shoulder can endure will have ballistic advantages hard to pass up.

 

[Ridge Runner]

There may be some merit to your analysis based on smaller shot sizes, i.e. 10, 9, 8, 7 1/2 for upland game birds, i.e. quail, grouse, partridge, pidgeon, etc..

However, for larger shot sizes 6, 5, 4, etc. the larger shot cup is required to increase the optimized amount of pellet, along with required increase powder charge to optimize pellet speed, penetration and pattern needed on game such as rabbit and squirrel.

Further consideration of such when hunting ducks, geese, swan, crane, etc. using non toxic pellet sizes 3, 2, B, BB, BBB, that are heavier than lead.

Then there is "Buffer" material that is used to reduce pellet deformation and stringing.

As such there is no 1 caliber do all rifle, there is no 1 do all size shotshell.

Recoil is recoil, be it ever so light or bone breaking heavy, it is the opposite equal reaction of the forward force. It can't be stopped, but it can be manipulated to be less felt.