French Gras question

[Patrick Chadwick]

So the sleeve includes some of the rifling?

Alas, no!

If you look at the linked info from Mr. Sedent, you can read that the problem is that the sleeve has NO rifling - after all, it would be horribly difficult to match it up and keep extractor groove etc properly oriented. The rifling would need to be cut AFTER the insert had been fixed in position - a very expensive one-off operation. The cm or so in front of the sleeve in front of the case mouth is thus normally plain, and typically has a diameter somewhere in between the bore and groove diameters, hence the "squeeze" effect and the undesirability of trying to use jacketed bullets. The only way I could think of to get a truly matching rifling in this stub would be to use an adjustable cutter set in a carrier that is lead-cast into the barrel (similar to the method used for lapping a tatty bore) and to proceed VERY slowly and cautiously, cutting each groove one at a time. That would be right royal PITA, so, as previously mentioned, I sold my "Grassepot" when I found an original Chassepot.

IMOH. JM, if your "Grassepot" has rifling right down to the end, then you are very lucky in profiting from someone else's long, patient work!