6mm A.I. fireforming

[AndyW]

I have new winchester 6mm Rem. brass all prepped ready to load. For a fireforming load would I pick a 6mm Rem. load and start at max? Fast or slow burning powder? I plan on using 70 grain SMK's as I have an abundance of these bullets.
Any help would be appreciated.
Thanks in advance.

 

[billmo]

You want to be very careful with begining with MAX loads from any manual. In order to blow out brass well the load needs to be fairly stiff but if you are jamming the bullets into the lands it is sometimes easy to get the load too hot. I would choose a medium burning powder to begin with. It is very difficult to advise anyone on these issues simply because each gun has it's own likes. If you have been handloading for a while just use good sound judgement. If not it may be a good idea to get with someone that has to accompany you locally. You are certainly doing the right thing by asking questions and this site is as good as you will find for info. Hope this helps. Bill

 

[Preacher]

You will be better off using a bullet that will engrave the lands when it's chambered, or open the necks a little to create a false shoulder and then size them so they go into the chamber with a crush fit if you have the tools to do it
Take the pin assembly out of the bolt and keep sizing till they have that little bit of resistence when you close the bolt...
A close to max load from the parent case with a medium burn powder is your best bet.
Keep adding powder till you have a fully formed case the first time out.........
If the chamber was cut the correct way you shouldn't have any problems with any weight bullet.......... and a empty case will have that crush fit your looking for.....

 

[AndyW]

Thanks for the replies.

Just recieved the dies today and should have the reamer in another week. Getting the 70 grain SMK out to the rifling should not be a problem as I requested the reamer to be throated for 75-90 grain bullets, as this gun is being built on a short action.

As far as the feel of a crush fit, approximately how far in to the lands would that be?

AW.

 

[Ackman]

The 6mm case has a lot of taper and blows out quite a bit so start with a max book load for the std. cartridge. Just like with any other cartridge, work your way up until you find best accuracy. Don't worry about powder "speed". Just load the same powder,s) that you plan to use with formed brass. Once you're fireformed, use that load as the starting point and go up again until you find the sweet spot. Winchester 760 works really well in that size case.

Assuming your chamber is cut properly, you should feel some bolt handle pressure when chambering an empty case.....it's the neck-shoulder junction hitting that part of the chamber. Seating bullets into the lands isn't necessary and it won't gain anything anyway. Don't jam the lands unless you're real good at remembering not to extract an unfired round from the chamber...... it's too easy to unchamber a live round and leave a bullet stuck in the barrel, which leaves the chamber/action full of powder, which means you're done shooting until every kernel of powder is cleaned out of there.

 

[AndyW]

Thanks for the replies guys.

Anyone shooting the 87 Vmax out of the 6mmA.I.?

Should it be possible to get to 3600 fps with the 87 grain?

Maybe 3800 fps with the 75 Vmax?

This gun is being built for coyotes, the 87 Vmax at these speeds should definately be a bang flop!

 

[wamin]

At those speeds the 87 Vmax will vaporize the internals and pounch a hole the size of a silver dollar on the other side of a coyote painting what's behind him red. :thumb:

 

[Cheechako]

Andy

Those V Max bullets are a lot more sexy looking, but give the 80 grain Sierra Blitz a try too. It is the best varmint bullet for the 244 AI, in my own humble opinion. More accurate than the Hornadys and at 3500 + fps, nothing walks away after being hit.

Ray

 

[AndyW]

Thanks for the input guys. The gun is currently being put together. I'll give a report once I get it working.