Can't Seat A 50 Bmg A-max

[caymangone]

Hello All,

Has anyone tried to seat a Hornady A-Max 50 BMG bullet into the case using the Lee Classic die and press setup? Because of the extreme taper of the A-Max bullet, the seating die doesn't fully seat the bullet before running out of adjustment. Anybody been through this yet? And if so, any fixes to this? Thanks!

 

[50 Shooter]

This topic has come up recently, I know there's a fix. I'll check the FCSA board and see what they did and post it here for you.

 

[50 Shooter]

Here's what a friend did for his.

If you have to seat the AMAX really deep, like for an 82a magazine or M2HB belt, then you'll need a custom seater stem. (or just fill it in with some lead or something) When I had my DTC dies made, I sent them an AMAX projo too and got one custom stem to fit that particular bullet along with the normal seaters in each die kit.

 

[caymangone]

Thanks for the info guys. I was checking to see even if I had to seat the bullet that far. I called Hornady and they said they seat it for an OAL of 5.73 inches! I don't see how that could work and give the appropriate head space needed. Other commercial reloaders are telling me they stick with the customary 5.45 OAL which is what most 50 cal chambers are designed for. I'm shooting a Barret 99. I haven't checked my chamber length yet but I'm sure 5.45 OAL is what needs to be used. All the commercial ball ammo I've shot through so far chambers and ejects fine. I just can't figure out why Hornady would be seating their cartridges that way. The other question surrounds what the powder load recommended is based on. Hodgdon recommends a starting load of 220 grains of H50BMG with a 'never exceed' of 233 grains for the A-Max 750 grain bullet. I assume they are basing those loads on a bullet seating to give an OAL of 5.45 inches.

 

[RecoilRob]

The A-Max has an extremely fine point (compared to military projos) and will not engage the rifling at anything resembling normal OAL. They can be, and need to be seated at a much longer OAL to have the ogive at the same distance from the lands as a normal round.

Many people single load the A-Max rather than stuff them so deeply into the case that they will fit in the mags.

I seat mine .375 into the neck for the AR-50 and it isn't anywhere close to hitting the lands.

 

[caymangone]

I guess the best thing to do if I want to shoot the A-Max is to measure my chamber length and seat the bullet accordingly. The next question is, how much H50bmg load to use.

 

[50 Shooter]

The best thing to do is to load some rounds with varying charges to see where you get good accuracy. Try starting out with a few loaded at 215 grs., a few at 216, 217.... You'll probably find that somewhere between 215 -220 grs. will give you the best results but you can check higher then that. I would use 235 grs. as a MAX load and wouldn't go any higher then that. Just keep an eye out for pressure signs when you get up to the higher loadings.

Once you find a good powder charge then you can start to tweek the OAL on the cartridge. Check out this site for some good reloading tips for the .50 BMG http://www.hevanet.com/50shooter/

 

[caymangone]

Well, after measuring my chamber length last night, I determined my optimum OAL should be 5.73 inches which happens to be what Hornady uses when they load using their A-Max. I took a spent casing, drilled out the bottom to stick a metal rod in, reamed out the neck so that a bullet can slide in and out with a little friction to hold it in place. I shoved the casing into the chamber and while holding the casing in place and using the rod, I shoved the A-Max bullet up until it stopped against the rifling lands. Then I carefully pulled the cartridge out with the bullet and measured OAL. I did this several times to ensure I got a consistent reading in case the bullet slipped a little while pulling the casing out. The OAL measured 5.82 inches. So, I will be seating accordingly and use the charge Hornady uses, 220 grains. Does this sound like a plan?

 

[50 Shooter]

Sounds good, the problem that I found with seating them that far out (5.82) is keeping the bullet in line with the case and straight. If you have a gauge to check run out, use it if you seat them this far out.

It's good to check any loaded ammo for run out as this is where your accuracy will start to be degraded from the beginning. Plus you can check the necks of the casings for run out....

One last thing, join the FCSA if you haven't already. Their magazine Very High Power (VHP) is worth the dues alone. Also keep an eye on their sister organization Fifty Caliber Institute (FCI) for any legal stuff on .50's.
www.fcsa.org
www.fiftycal.org