Brass life from AR platforms?

[Hawk45]

I'm currently considering an AR based platform in 3 possible configureations (6.5 Grendel, .260 , .308). I like the 6.5 Grendel b/c I can use on my existing AR15 lower. The 308/260 ARs would be new complete rifles of course.

My question is what is the expected brass life with a semi-auto? With my bolts I FL size once and just neck size from then on out .. at least till they get to tight for the chamber. I can get 12 or more reloads out of brass if I don't run them hot. With the AR platform it seems you need to FL size after every use.. how fast does this wear out the brass? Will annealing help them last longer with FL sizing? I just started doing this with my bolt brass.

Thanks,
Hawk

 

[saleen]

Re: Brass life from AR platforms?

I'm still getting started with the 5.56 reloading platform, but I've been told that the biggest factors in maximizing brass life is starting with quality brass, and not resizing them excessively (meaning no more than necessary to bring them into spec.) I was also advised to re-anneal them after 3-4 loadings, but I haven't gotten through my initial 1000 cases of new LC 09 yet so I haven't experimented with that yet. It might also be wise to "tune" your ejection down a bit to minimize the damage done by the case deflector. I also use a brass catcher religiously to avoid beating the cases up or getting them walked on. The fact that it makes policing them up a snap is just a bonus.

A fellow shooter told me to expect 8-9 loads, but my gut feeling is that that seems a bit optomistic. Time will tell.

I've gotten 9 reloads out of Lapua brass in 7.62x54R (SVD), and I think I pushed that a bit further than I should have. Nothing bad happened, but gun isn't kind to spent cases and that last loading made me a bit nervous. Accuracy didn't suffer though.


Saleen

 

[MitchAlsup]

Re: Brass life from AR platforms?

In an AR platform, brass life can be great or terrible, depending on when the action opens up and begins the ejection cycle.

Me, I load a medium weight bullet (69 gr SMK) at medium pressures (24.6 gr Varget) and get both nice accuracy and long brass life (high teens: LC cases).

My intention for this load is "inside 600 yards" as I have a 308 for longer range stuff.

One of the interesting properties of the AR platform, is that as you change the chamber pressure, the gun changes where the case gets thrown. In my AR I can get the cases to land in a 1 foot circle right off my right sholder about 3 feet away. As pressure increases, the cases are thrown farther back, and as pressure decreases they get thrown farther forward. You can almost use where the case got thrown to determine how much pressure was used.

 

[MALLARD]

Re: Brass life from AR platforms?

my cases get little vertical scratch marks on the case neck from ejecting ( i think from contact with one of those locking lugs )

does this happen to anyone else ?

 

[Zanshin]

Re: Brass life from AR platforms?

One of my match rifles does. Two vertical scratch marks from ejecting. The rifle is accurate and the brass doesn't seem to be any worse for it so it never bothered me that much.

 

[littlerascal56]

Re: Brass life from AR platforms?

My Armalite AR-10T left a dent below the neck, scratched up the case head, and sometimes dented the neck slightly. I used WW brass, but decided that Lake City was good enough for most shooting.

My RRA and Wilson Combat M4 were pretty tough on .223 brass also. The worse was my SIG556 SWAT...It DESTROYED brass after 1 firing.

Bottom line is the gas guns will damage the cases to the point you will discard them before the act of reloading wears them out.

All my match cases only go in my bolt guns.