Cheapest way to convert 10mm LS to 40?

[shawnba67]

I have a match in 9mm I have been using in limited division uspsa. I bought a 10mm LS on gbroker. With the cost of 10mm brass and availability I'm looking into a 40 option. I like the idea of getting a 6in barrel and adding an extension (compensator like style without the barrel ports) to extend the sight radius. I have 2 k10 mags, the price of mags would factor into this final cost number I need 3 total.

[kneelingatlas]

It's sounds like you've got a plan all worked out. The 6" barrel runs $185 from EAA, and I suggest Numrich for the comp ($42). You'll also need a custom guide rod to index the comp.

[shawnba67]

What about the mag's? can I run 40 thru my 10mm magazines? Would i have to load them long? Any one have any luck with this?

[Intercooler2]

If they shoot .40 in a G20 out of the same 10mm barrel it should work in a Tanfoglio.

[shawnba67]

Got to wondering if 40 long might be the cheapest answer. Load a heavy bullet out as long as possible. In mine a 180 MG JHP hits the rifling at 1.280. guess it would out of 40 brass also????

[Gary1911A1]

Got to wondering if 40 long might be the cheapest answer. Load a heavy bullet out as long as possible. In mine a 180 MG JHP hits the rifling at 1.280. guess it would out of 40 brass also????

I wouldn't try this as with your bullet touching the rifling will increase pressure and if you load 40 long into a 10MM barrel the extractor will be the only thing holding the round when the firing pin hits the primer which is hard on the extractor. Try to get a .40 barrel.