I just chambered my first gun. Mauser. Bought a short chambered .35 Whelen, but bought a .35 AI reamer and headspace gauge. Bolt closes on gauge no hangup.

Bought some .35 Whelen brass, put through the resizer. Most of the brass is very hard to close the bolt on. Is my chamber just short, or is it the headspace/shoulder difference that is talked about for the standard Whelen?

I though all AI cartridges could chamber and fire standard brass. Isn't that true?

But I also read AI shells are a tad bit shorter.

If anyone can, please advise. I am ready to load.

Jerry