Shoulder Angle on an AR cartridge

[MGYSGT]

Wanting to change the shoulder angle on an AR cartridge. Wanting to increase it as much as possible (think AI) without creating a feeding problem from the magazine in Semi-Auto rapid fire. Most semi-auto have a 23 to 28 degree angle of the shoulder. What is the best I can expect from a 6.8 with the shoulder moved forward by 50 thousands and still have reliable feeding from the magazine? 30 35 40 degrees????? Anyone done it?

Tom

 

[mac86951]

It's more than just shoulder angle, it's location of shoulder to OAL length etc...

6.5 Creed feeds just fine, and I've heard of some with 6mmBR feeding as well.

Next challenge is feeding when dirty. I doubt 6.5 Creed is going to feed as reliably when rifle is dragged through the mud and cleaned occasionally through the decade.

For something that will be carefully handled, 223 AI should work just fine, but I'll think harder about a self defense gun.

Not sure of your intent or purpose, so please let us know if that resolves your question?

 

[MGYSGT]

Target shooting. Bench/Prone/Offhand/Sitting

Tom

 

[Ggmac]

Benefits would probably be less than expected for the experimentation needed .
As mentioned it's more than just angle . Bullet length ( OAL ) neck length etc .
If you can do ALL your own work , chambering , threading , drilling port size ,etc , it may , may be worth the few exta FPS . I doubt it .

 

[mac86951]

Question, why not choose a target caliber that is already in production? 6mmAR or 6.5 Grendel for example. Not a lot of target bullets in 6.8mm

 

[MGYSGT]

Sorry to mislead you. Didn't mean to. I am going to neck it up and shoot short fat bullets at 300 yards and less in local shoots.