doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 2 3/4 shells in 2 1/2 chamber?

I agree, in point. I have 5 older 12 gauge LC Smiths, fortunately, no cracks in the locks or tang areas- but I only shoot 1 ounce 1150 fps loads in them--except for the Ideal LONGRANGE and the Eagle Live Bird gun, both with 3" chambers and the under rib reinforcing yoke-- in those 2 heavier 12's I will use 2&3/4" AA Handicap Trap loads at 1250 fps. and 1& 1/8 ounce shot loads--as well as the 1 ounce loads when I am shooting barn pigeons and pest birds for practice. . I can't state this as gospel truth, but I believe one reason these Smiths have remained intact and stock cracking free (their Achilles heel) is from my religious usage of only lighter loads. My 2 cents worth--

G. T. Thomas touched on this back in the late sixties. He noted that:
1) The primary danger of using long shells in short chambers is not interference between case mouth and forcing cone, but the higher pressures associated with the longer cases, and
2) His own tests with 2.75" Eley Grand Prix loads in 2.5" and 2.75" chambers showed no increased pressure in the short chamber - in fact, the short chambers recorded slightly lower pressures.

If the hulls in question are premium plastic, the mouths are generally on the order of 0.005" thick, compared to 0.025" for paper, there is considerably less material out front to cause obstruction. A plastic hull might smooth the transition from chamber to bore if it doesn't actually allow everything to open into the forcing cone before having to constrict again going into the bore.

The British ammunition makers did a thorough study of this back when fold/pie crimp shells were introduced.This was well covered by Burrard long before either Thomas or Bell delved into it. As a result of their study all fold crimped nominally 2�" shells were put up in a longer case which would have a similar loaded length to the 2�" roll crimped case. Had the same length case been kept wad space would have of necessity been reduced plus it was feared the shorter loaded length of the fold crimp shells would be confused with a 2" sheel & fired in those still shorter chambered guns. This work started just prior to WWII & was finished shortly thereafter.
Unfortunately it seems neither Thomas nor Bell read all that Burrard reported & totally misquoted him on this subject. They cited older writings of his in which he emphatically denounced firing the longer shells in short chambers. This was of course from the days when the longer shell was still a roll crimped shell carrying a heavier load than the shorter chambered guns were designed for. At the time it was written it was "Sound" advice. As soon as the further work was done of putting the 2�" load up in the longer shells with fold crimp he amended his earlier Warnings & in fact himself stated that the important factor was the load & not the length. He did further warn about using a too long roll crimped case in which the loaded shell length exceeded the chamber length & would be forced into the cone, still good advice.
It has always been a mystery to me why an old RedNeck HillBilly like myself could understand what Burrard reported on this, but neither Thomas nor Bell seemed to be able to, thus their stated Confusion & Misquotes.

With the ease of loading 2 1/2" shells, why even bother trying to shoot 2 3/4" in these fine old guns. I have MEC 600's that were bought off the sale board at ranges for $50 each(16ga and 12ga) that I put short shell kits on plus roll crimpers. I load 3/4 oz target and ITX loads and 1oz NP BB's and 2's for coyotes in the 16ga and skeet, SC, upland and waterfowl loads in the 12ga. I shoot 2 1/2" shells in ALL my 12 and 16ga guns even if they take 2 3/4' it is just easier that way.

I do miss the 1oz B&P High Pheasant loads though.

I think you (or Cheditte or whoever) mean FPS not psi.

BTW I've had good luck with the Herter's 16 bore 1 oz. loads in 8s and 6s going 1165 fps in 16 bore 2 3/4 proofed doubles French and English. Seat of the shoulder seems they kick less than their Federal or Remington counterparts. Is it the straight walled hull?

Many "Economy" or "Dove and Quail Loads" kick far more than their payload and dram-equivalent skeet loads. Also I've found some use metric primers in SAAMI hulls. A good way to take your double gun off the face unless it's a Darne.

You are correct and thanks. It is listed correctly on the link.

The 20s aren't known for the problem of empties hanging up in the ejection port-the 16s, are. You can feed my first year 20 anything, and it works just fine. Never seen the problem on a 20 or a 12. No modifications on mine save a lefty safety.

Model 12s can break the firing pin and leave the broken point projecting from the bolt, which will cause the gun to fire before lockup is complete, with spectacular results. Does it happen a lot? No, but, more often than it does on any other shucker.

Gospel truth, lad.


Best,
Ted

Hard to Imagine anything like that could happen on "The Perfect Repeater".

I have 11 older (pre-1950) Model 12's and have shot the living piss out of each and every one over the past 50 years. Never have experienced a broken firing pin, or needed to replace any parts except a cracked buttplate- I agree with Ted, I did take the Model 1912 20 gauge out for barn pigeons (mild weather still here in MI-not great waterfowling yet--and shot two boxes of AA 7/8 ounce skeet loads through it- works like gangbusters, just getting used to the straight hand stock-the only Model 12 I have ever owned or shot with that unique feature. Makes me think of the Havilah Babcock story "Slim Boggins' Mistake"-- as I visualize the main character of that great quail huntin' fable as shooting a similar Model 12.

But, Murphy's Law rules supreme in our world, and anything can fail or break over time, and it is true, if a broken firing pin tip protruded from the bolt face and the bolt was closed into battery on a live round in the chamber- not a good thing indeed. One of many reasons to always have that muzzle pointed in a direction so if that did happen, the worse case scenario would be a schmidtload in the BVD's--