old gun, new shells

[Clark McCombe]

I might leave the GHE and the 20 ga alone but the 12 ga Trojans and 16 Trojan I like to shoot.
Any recommendation on who could do the work?

[Dean Romig]

Originally Posted by Clark McCombe

I might leave the GHE and the 20 ga alone but the 12 ga Trojans and 16 Trojan I like to shoot.
Any recommendation on who could do the work?

You can certainly shoot 2 3/4” ammo in a Trojan without lengthening chambers. I’ve been doing it in all of my Trojans since 1961…





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[edgarspencer]

Your picture seems to me to show your chambers are 2 5/8", intended for 2 3/4" ammunition.

[24 grams]

Even 20 gauges?
I just bought an O frame 20 gauge Trojan shooter with 2 1/2” chambers.

[Bill Murphy]

Mike, regardless of what your recipes call for, I use any wad that fits in the shell and doesn't hang out the front. The wad I have been using for a few hundred 2 1/2" RST 7/8 ounce loads is a green wad with short petals, don't remember the brand. The loads are beautiful with flat tops. I have two other wads that are identical to the green one in height, one pink, and the other WW Grey.

[Mike of the Mountain]

Originally Posted by Bill Murphy

Mike, regardless of what your recipes call for, I use any wad that fits in the shell and doesn't hang out the front. The wad I have been using for a few hundred 2 1/2" RST 7/8 ounce loads is a green wad with short petals, don't remember the brand. The loads are beautiful with flat tops. I have two other wads that are identical to the green one in height, one pink, and the other WW Grey.

If they fit in the hull and allow for a good crimp then more power to you. Speaking for my experiences, using standard wads in my 2 1/2” hulls did not result in good crimps. The majority of my 2 1/2” loading is with 16g hulls. I do load 12g too and use short wads for them too.

[Craig Larter]

From Sherman Bell's Article in the 2001 Winter DGJ Long Shells in Short Chambers
“Shooting 2 3/4” shells in 2 1/2” chambers does make them produce more pressure-but in most cases it is less than a 1000 psi increase. I see no reason, related to safety, to modify an original 2 1/2” chambered gun to shoot 2 3/4” shells, if the 2 3/4” load you intend to use would develop pressure that is safe in that gun, when fired in a standard chamber!”

[Drew Hause]

Craig: as you know that statement was based on a study of 12g shells
https://docs.google.com/document/d/1...A/edit?tab=t.0

We have NO data regarding using long for chamber 16g or 20g shells.

Again, some modern nominally 2 3/4" shells are shorter than 2 3/4". It was recently reported that Aguila 16s were short
https://trueshotammo.com/ammunition/...1-oz-1200-fps/

[Clark McCombe]

Are Manufactures supposed to release the pressure for their various loads?
I've been using Fiocchi 12 ga 2 3/4 " 1oz 1250 fps 7.5 shot shells in an $800 Trojan which I found out yesterday, when I got my little feeler gauge, only has 2 1/2" chambers.
I immediately switched to using RST 2 1/2" shells.
The Fiocchi cost $120 a flat
the RST $230 plus shipping.
I can:
Practice with an old Remington 1100 I have, which I would rather not do.
Have the chambers lengthened on the Trojan.
Continue to use the Fiocchi in the 2 1/2" chambers.
Or be distracted by the thought that every time I pull one of the triggers it will cost me a dollar if I switch to the RST, and accept the fact that using the old gun I like will cost me.
Your thoughts please.....

[Drew Hause]

The U.S. makers decline to provide pressure data, and with the exception of Tom Armbrust, those doing ballistic testing won't test factory loads.
Most of the Italian makers do.
B&P Comp One 28 gm is only 6530 psi

IMHO it is likely your 12 g chamber is 2 5/8"
There is an easy way to measure chamber length using a 3" x 5" index card, rolled lengthwise, and slid into the chamber. It will partially unroll and expand to the chamber diameter.
Gently advance the card until it stops at the end of the chamber (where the forcing cone constriction starts), use a pencil to mark the card at the breech end of the barrel, and repeat the steps to see if it always comes to same spot.
Then use a ruler to measure the length marked on the card.
The chamber must be clean, and it works best with a new 3” X 5” card.

Let us know what you find.
If 2 5/8" (and I recognize we're quibbling over 1/8") pick a 1 oz at 1200 fps, shoot and be happy.
It's more difficult with 16g and 20g loads.