5.56 load

[glock63]

Heres a pic of a 20 round group shot yesterday with my SPR at 100 yds. According to my caliper, it measures approximately 1.75.

The load consists of 26 grns ramshot tac, mixed brass full length resized, a 60 grn vmax bullet, and federal primers.

There was no wind, and the temp was about 70 degrees F. Im far from the best shot, and most of the vertical dispersion is probably from me. Any ideas on how I can improve this load?

 

[fusiachi]

Re: 5.56 load

There's no way to get 60 gr. of any powder in a .223 case. Google Optimum Charge Weight if you're interested in a systematic approach to developing a load for your particular rifle. Also, the capacity of .223 brass varies significantly by headstamp. At best it's going to make developing a consistent load difficult; at worst it could create a hazard as you approach max. loads.

 

[glock63]

Re: 5.56 load

Your correct. I meant 26grns. Corrected in original post. Im aware of the differences in brass capacity. That probably played a part in the vertical dispersion as well. This will be a general purpose plinking/varmint load. Sorting brass gets old when shooting 200-300 rounds per session, and I will not be shooting any competitions with this load. I will try a batch with CCI benchrest primers I think.

 

[cinosbus]

Re: 5.56 load

I would probably try 24 or 25gr of TAC instead of 26 with the 60gr. That's pretty hot for mixed brass IMHO. Also try the 50gr V-Max instead with 26gr TAC - this is a "pet load" that works for many. Sort the brass by head stamp. Let the barrel cool every 5-10rds. Subscribe to the on-line training section and practice.

That's what I'd do.

 

[glock63]

Re: 5.56 load

Do you believe the 50grn vmax would shoot as well as the 60 grn in a 1/7 twist barrel? I will try backing the powder charge off a bit too.

 

[fusiachi]

Re: 5.56 load

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Do you believe the 50grn vmax would shoot as well as the 60 grn in a 1/7 twist barrel? I will try backing the powder charge off a bit too. </div></div>

In my experience, no. In my Sig 556, 62 gr. handloads group around half the size of what I can do with factory 55 gr. ammo like XM 193, and 77 gr. SMKs produce even better accuracy. I've gotten better results from bullets in the 50-55 gr. range by detuning the loads down to around 2700fps. or so, but needless to say they're pretty worthless beyond a hundred yards or so.

 

[cinosbus]

Re: 5.56 load

Yes, I think the 50gr would shoot better than 60gr - regardless of twist. The XM-193 will only shoot into about 2" on a good day for my rifle, but 50gr V-max will shoot under .75MOA all day long, any day in my 1:9 AR.