I believe this is an unmodified 1874 French Gras (all # match) made in 1875
closeup of Receiver
close up of Rosewood insert/cartouche'
OK, I was gifted this by my Liberal Brother about 2 decades ago. The story is he traded this gun for a bottle of Wine with his Boss (a long time firearms collector) at the time. The Boss's new wife wouldn't allow guns in 'her' home, So I guess the boss brought his large collection into the office, I guess every closet had some guns...and a bunch of guns in the trunk of his car too.
He had told his Boss about my budding gun interest and my brother asked him if he had a gun I couldn't shoot...well they worked out a deal with this Gras cause the Boss said it'd be immpossible to get commercial ammo for it. My brother thought it'd be funny if he gave me a gun I couldn't shoot.
Well, after I got it (and without the internet mind you) I did some research and found a custom ammo manufacturer that could make a box of ammo. Well $40 and a month wait and I was at the range taking a photo of me, the rifle, and a puff of black powder smoke coming out of the rifle...and sent a copy of the photo to my Bro.
That was 1993, I think? I only shot it twice, So today I still have the box of 18 rds with 2 empties.
The First question is, why is my Bore larger than all the research says it should be ?
sluuging results below.
This link (while about a Chassepot converted to a gras configuration is about the best info I could find)
OK, about 2 months ago, I slugged the last one inch of the muzzle, groove dia. was .455 while the bore was .436 I thought great, I can use a 45 colt boolit and was just gonna roll with that. I kind of put this project aside for a while. Then I stumbled onto the above link.http://britishmilitariaforums.yuku.c...1mm-Gras-Loads
SAFETY WARNING!
Watyrell, I too have a "Grassepot" - A Chassepot (Mle 66) upgraded to a Gras (Mle 74). In fact, it also has the later Gras upgrade whereby a gas escape channel was milled at the front of the receiver (Mle 80), making it a Mle 66/74/80. Take a look at your example, it may have this modification as well.
The Chassepot-Gras conversion was done by machining out the Chassepot chamber and inserting a sleeve to tak the centerfire cartridge case. Looking along the barrel from the chamber end, there is about a 1 cm section between chamber and start of rifling that is TIGHTER than the bore. Puzzled by this, and worried that I had bought a dud, I contacted a French authority on the care and feeding of the Chassepot-Gras family, and received a very detailed answer (in French) which says quite clearly that this was a result of the sleeving process, and it means that you SHOULD NOT TRY TO FIRE A BORE-DIAMETER BULLET IN A 66/74.
I seriously recommend that you slug the bore before makaing any further experiments. If your rifle is like mine - and according to the French expert, it most probably will be - then this section between chamber and rifling will swage down the bullet to about 11.2 mm, or about 0.441". The 66/74 rifle relied on bullet UPSET to function properly.
Another friend actually gave me an original Gras cartridge loaded with a jacketed bullet. And the bullet diameter was indeed 11.2 mm on this example.
So please, do NOT follow the conventional wisdom that bore diameter bullets are always best. In this case, the result will be serious overpressure in the chamber. Not good for your rifle - or, maybe, you. Using soft(-ish) lead bullets, the advice that I received was not to go above 11.25mm (0.443"). In other words, the 0.443 Mauser bullet will be satisfactory. It will be squeezed down a little in this curious throat constriction, and will then bump up when it hits the rifling, PROVIDED that it is not too hard.
Sorry for all the capitalized words, but I did not make all this up, and the guy who really knows about "Grassepots" is Jean-Pierre Sedent, of the shooting club at Lezignan-Corbieres, where I shall actually be shooting in May, so I shall try and get more detailed info from him, if any is available. Until I can report back, please take the aboves a serious caution! Patrick
So, today, I slugged the first one inch of the throat/bbl. the groove was .454 with the bore at .436
Then I pushed a slug through the entire 32" bbl starting at the throat. I felt no constriction as mentioned in the above link. I felt equal resistance till the last 12" of the bbl out to the muzzle, that was much easier, but still slightly resistant. It measured the same as the slug from the throat .454 groove and the bore is .436
I measured and re-measure the slugs on all sides, to be sure I was reading it right, I found no concernable variation (Mitutoyo 1" Mic.).
another fun fact, the two fired cases from 20+ years ago, measure .451 inside the neck.
FYI, The boolits in the custom ammo I had made 20+ years ago seem to be unsized and quite out of round. .437 - .446
So I plan on using a 300gr. soft alloy boolit sized to .454
pushed with about 10 gr. of Unique (I'll probably start with 8gr.)
I figure if that loaded round will chamber I should be good.
if NOT, I will then try sizing the boolit smaller
Please feel free to comment, any help is appreciated.
Thanks,
Jon
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