Advice on 223 Remington load with short seated Sierra 80 gr MatchKing?

[LRRifleman]

Good morning. I just discovered yesterday that with my long range AR in 223 with a Wylde chamber, I need to seat my bullets to a C.O.L. of 2.465 to avoid engraving of the bullet and allow the bolt to go into full battery. Being disabled, I am now competing in mid range and long range F class matches. My rifle has been semi competitive with 77s, but I need the 80s for 1000 yard matches.

Has anyone had experience short loading sierra 80s over either AA2520, Varget, or H335 and have a load they care to share? My AR has a White Oak match upper with a 26" 1:8 Wilson.

Thanks, Ed

 

[sinister]

A new Compass Lake or White Oak can go as short as 2.450 depending on throat condition and leade angle.

With a 26-inch barrel I'd hover around 24.0 of Varget -- higher than that and the longer barrel (with a standard-length gas tube) might give you some pressure issues. You might consider a Heavy Buffer or Carrier Weight System if your brass shows pressure signs.

The 80 SMK at 1,000 is certainly do-able and challenging. You really have to keep up on your wind calls.

 

[LRRifleman]

Thank you. I have been trying 24.4 of Varget with the 80 loaded to 2.550 with a velocity of just over 2800, fired at 49' ASL. After I found out from White Oak that I needed to shorten my C.O.L. to 2.465, I was on the phone to Sierra, where they suggested my experimentation a grain below what I had been trying, and work from there. Honestly, I hate the idea of reinventing the wheel as a guinea pig. Looking here to find out what range people are finding safe success in.

 

[sinister]

I've gone as high as 25 of Varget at 2.500 with a Tubb Carrier Weight System, but that's from a USAMU-Krieger 20-inch National Match service rifle. Without the carrier weight you'll get some bright ejector smear on the case head face and flattened primers.

 

[gstaylorg]

I've been shooting Berger 80.5s out of a 26" bolt gun, but also loaded very short as you're describing in your setup. I tried several different powders before stumbling onto H322. With a [relatively] short barrel and bullet seated deep, the faster-burning, higher energy powder gave me much better results than H4895 or Varget. H322 is also very fine-grained and easy to measure.

Unless someone has a very similar setup to what you're using (Wylde chamber, 80 Sierras, very short seated is probably not so common), I suspect any charge weight values posted probably may not be very useful. The key to making that setup work is likely going to be the choice of powders. I would start by finding a powder that will give you the kind of velocity you're looking for, without going way over pressure if possible. Once you find one, a normal load workup will get you where you need to be.

 

[bohem]

I like IMR 8208 XBR or BLC-2 to get the speed from heavies in a 223. I'm using 82 Berger BT's in my 18" bolt 223 for distance work because the price point is essentially the same as an 80 SMK with a substantial increase in BC.

If you're interested, send me a PM and I will trade info, we can talk about it and I should be able to get you dialed on the right path very quickly.

 

[Rprecision]

Commercial .223 brass often have greater case capacity which could be useful in what your trying to accomplish.

The problem then becomes thin brass sometimes doesn't stand up to being pushed like 5.56 brass does.

Ramshot tac is also well know for 77 and 80s