Took my G2 to the range today with a box of DoubleTap Ammo in 45-70 and found that the cartridges would not fit. (could not close the gun) I gave them a call and they said that because of the large size of the bullet , in some guns the bullet will contact the end of the chamber too soon. The fella' I spoke with said I could return them but also suggested having the chamber lengthened slightly. Is the gunsmithing involved worth the effort, time , and money. I'd kinda' like to try this ammo.
By the way, the guy at DoubleTap was very congenial.

Do they note that subtle inconsistancy on the ammo box or the sales ad?

Not that I noticed, no.

Here is a quote from their ad:
"A 45-70 load that will deliver superior penetration on big game and remain safe to shoot through all guns chambered in 45-70 (except the old trap-door style)."

Archr,

Have you had any other ammo cause this issue? And probably more importantly, how does your previous ammo shoot in your barrel?

If you're getting accuracy from other loads, I wouldn't have the chamber reamed for unknown performance out of a new load.

I have some frames and barrels that just don't get along well - do you have another 'Tender frame you could try with that barrel?

If your gun will chamber any other factory loads, I sure wouldn't alter it for theirs.

Do you have a caliper that you can measure the case length with? If it is a bullet thing, go with a lighter bullet. If the case is too long, it is a different story.

The 45-70 barrel is new to me so the only loads I've shot so far are Hornady's Leverevolution 325gr and they shoot just fine. After sighting in they go where I point them if I do my part.

I don't have another frame as this is the only Tender I own.

I also don't have a caliper but the case of the DoubleTap is visibly longer.

And since I don't reload "yet" can you guys recommend another cartridge with this type (flat nose hardcast) of bullet.

The hornady case is shorter than SAAMI to allow for the longer FTX bullet so you need another example to compare against.

You might want to give Reed's Ammo a jingle as they will load nearly whatever you want in there.

My guess is that you were shooting the 400gr. WFNGC Hardcast bullets.

This is not all that uncommon of an issue with these wide meplat heavy bullets. I have the same issue with my bullet seating dies when using this profile bullet. Reaming the chamber out a bit is not all that big of a deal and could be accomplished pretty inexpensively and quickly by any gunsmith. You don't need the whole chamber reamed out so much as just a hair of extra length to allow that bulldozer of a bullet to fit.

My guess is that you will find this issue with just about any wide meplat heavy bullet regardless of the manufacturer.
The jacketed soft point and hollowpoint bullets taper more and thus allow the front of the bullet to enter the rifling without the hangup issue.

T/C uses what is known as a no throat chamber. This is due to many users of the short light 300 gr bullets that are loaded in 45/70 factory ammo.
My Encore 45/70 barrel is the same. I even have to go shorter on OAL with the Speer 400 gr FNSP than the manual lists.
With wide nose ammo and some with a front drive band that is wide one will encounter this situation.
One will have to live with it or get the chamber that SSK puts in their barrels.
A day in the life of a T/C owner is all this is. If you reload just a small bump in the road.