First off, I do not want to shoot 1 5/8 1500 fps mini mag load. Looking at a Francotte 12 bore proofed 12 gaguge, 2 3/4 inch 3 1/4 ton. It is the Knockabout model with ejectors.

I am looking for a 12 bore that is safe with what I have always read as the pegion load of 1 1/4 oz no 4 shot at 1200 fps. I have noticed ammo manufacturers have stopped marking their boxes with ton.

Gun weighs 7 pounds and on my choke gauge is chocked IM in both barrels. The gun is on face very clean.

I do not have a picture of the barrel flats. Like a dumb ass, I drove away with out getting a picture seller is emailing them to me.

The gentleman at Griffen and Howe (owns the ledgers where Francotte was imported through AF and VLD) told me any modern 2 3/4 inch load meet that proof, but to stay away from real heavy loads which I take to mean mini mags 1500 1 5/8 loads or 1 1/4 1350 loads.

I called RST ammo. The lady there converted 3 1/4 ton to 6500 psi and told me there lights 2 3/4 inch loads are above that. I am not trying to run the lady down, but I know it is not a straight conversion like that.

I also know that 3 1/4 ton equals 850 bar in British speak but do not know what that equates too.

One last question is cooper plated shot safe in this gun?

850 BAR is low.
12 ga 2-3/4 & 3" loads nowdays are 1050 BAR.
which is in the 10-11,000 psi area.

the 3-1/2" loads are higher pressure [15,000]

at your lower pressure you'll be looking at 1oz type loads in the 1050 fps speed area.
that isn't a pressure guarantee, just a safer bet.

your best bet is to make your own using pressure tested data.

Thank you sir

A conversion chart gives me 6500 psi for 3 1/4 tons.

quote:

One bar is equivalent to 14.50 PSI. PSI stands for pounds per square inch and is a common pressure metric in North America

AFAIK Winchester still makes 1 1/4 ounce pigeon loads. They were commonly shot at duh! pigeon shoots when I was attending them. IMO, they would be a pretty hot load for an old double.

i'll throw a little more information at you so you can understand the situation.

back in the day [when your gun was made]
the shot shell loads used two pressure lowering
factors out of necessity.
the first is the roll crimp which will lower pressures by 1500 psi [if nothing else in the load is changed]
and they used fiber wads/gas seals, not the efficient plastic ones common today.

this is why target type loads back then used 44grs. of stuff like 'BULK' powder by DuPont,
they needed to, just to generate enough speed in the load.
today with a fold petal crimp and a plastic seal [wad] you can get to that same 1150-1200 fps as the old 2-1/2 & 3 dram [black powder]equivalent loads with 17-18grs. or 20-21grs. of powder but of course the pressures are higher.

remember modern shot shell powders pressure spike rather quickly, generate their gas, then are done.
but there is a broad range of them to work with so pressure doesn't show up based on velocity alone.

Thank you gentlemen. I have seen the 44 grain bulk DuPont reference. Like most things with no reference to a modern equivalent I get lost.

I asked and appreciate your knowledge. RST called me back unsolicited. The gentleman informed me they had 3 1/4 ton loads. I like the gun a lot. Still gathering info and will take any knowledge offered. You guys have the knowledge. I am the one who had to ask. I think I will call Hodgens and get some thoughts on loading to match the proof. Hodgens has always answers my questions in the past.

As Mr. Lamar has said modern smokeless loads give equal velocity but with higher pressure. I guess what I am trying to figure out is what Modern loads are equal to the 3 1/4 ton rating. I do not want to abuse the gun or buy something that does not meet my desires.

I am satisfied and happy with the RST communication that they have safe loads that deliver what I want to shoot that equates to 3 1/4 ton. I am leaning toward buying the gun.

As to that board range with pressures being equally board, I have never hunted anything in over a decade now but turkeys with a modern 3 1/2 10 gauge all loads are the same. Stopped by my favorite local dealer man there are a lot of these short 12 gauge loads.

Thank you all.

You might want to check this out:
http://www.16ga.com/forum/viewtopic.php?t=3428
It looks like 'tons per sq inch' falls in to the same area as LUP, CUP., etc., not a direct translation to psi. They did the best they could with what they had at the time but modern technology has improved things quite a bit.
C.G.B.

Wonderful information Mr. Bagh. This does underscore one pitfall this info reports 3 1/4 ton as 900 bar. I know I have read 3 1/4 ton as equaling 850 bar. Everyone seems to report something differentT hey have provided a good citation for their info and appear to know what they are talking about. An once of caution as suggested in the material is worth more than an extra tenth of an ounce or 100 fps.

Just got off the phone with Hodgen. They also have load data under 8k and 9 k psi that makes 1 1/4 oz load through full choke. Well within the safety margin provided by Mr. Bach's information. Based on this, RST, and Griffin and Howe communication I will proceed with buying the gun.

I know this was an entry level gun. But it looks like what I think of when I think if a shotgun of this type. It is choked well abd the ejectors are a plus. I love the worn period correct butt pad and not one of those silly ventilated things that seem to be on everything thing.

Now, how to keep my wife from noticing. Any suggestions.

I got a couple of tricks for getting guns in the house.
I find it easier to just have the wife go pick the gun up at the store.

You need to be careful when converting ton units of pressure. The English usually used the old long ton which is 2240lb not the short ton which is 2000lb.

3 1/4 ton is 7280psi if referring to the long ton and 6500psi if using the short ton.

There is often debate on converting PSI into Ton or both into BAR or Atmospheres with some saying it is not a direct conversion of units. I have a letter in my possession from correspondence with Norma in relation to the ballistics of the 404 Jeffery ammunition they produced under the Parker Hale banner and they used direct conversions of PSI and Atmospheres for pressure corresponding to the old 16 Long Ton standard load for the 404 Jeffery. Good enough for Norma, good enough for me.