9mm Freebore

[pau605177]

I am installing a new Schuemann 9mm AET barrel in my 9mm major. I have two questions. These barrels are already finish chambered. What diameter should the freebore be for .355 bullets? It seems the freebore is a little snug. Both factory rounds and my own loads require a little push to fully chamber. The bullets clearly show drag marks from the freebore area. I would think you might want .0005 -.001" clearance in this area?? Second, the rounds I load are around 1.190 OAL length, should the free bore be lengthened by the same amount I have increased the AOL of the cartridge?

Thanks

Paul

Edited November 17, 2008 by pau605177

[rider82]

Pual, I just ordered the same barrel, it was my understanding that you should have no problem loading to 1.2. Interesting to see the other responses, but I would definately avoid loading into the lands.

[speculatorking]

Is your barrel an AET Ultimatch? I just got one too.

Edited November 18, 2008 by speculatorking

[Aristotle]

I've got a Shuemann AET Ultimatch in .355 and 1.190-1.195 would not load reliably for me with several FTF. I dropped my OAL down to 1.175 and the gun just gobbles them up.

[Radical Precision Designs]

I do wholeheartedly endorse the Schuemann Ultimatch AET's.

Like any barrel that has to be finish fitted, you will likely have to fit the hood by cutting down in it some. The factory can not tell how much you'll have to cut. Even though all AET barrels are already finished chambered, you may have to slightly re-finish ream the barrel to compensate for any fitting cuts or for function feeding discrepancies, and tuning. This includes any additional "throating" that may be needed to suit your ammo. Normally very little is needed if at all, but you can not take for granted that because the chamber is "mostly" good to go that it will be so.

[pau605177]

Actually this barrel went in a high mileage gun. The barrel went right in. No fitting required (feet of course). It went right in! Not loose though. No cuts on hood length required. Chamber should be good. We all know Wil Schuemann knows what he is doing. Free bore however may need a little something to accomidate longer rounds. Wil recommends .200" of free bore. This is for a standard length 9mm round. Does anybody lengthen the free bore for 9mm major loaded out?