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Former11B
13 November 2015, 19:06
I will say it's hard to take pictures of everything when your camera dies after the first photo, due to a battery that wasn't charged, but all the info here is well documented and I've tested A FREAKIN' LOT of charge weights with this bullet to find the node my rifle shot the best. After three other range outings also shooting 69gr SMKs with no decent results, I was starting to think either I was off or the barrel was bad. And when 68gr OTM Black Hills rang in at close to 2"....lets just say I was wondering if shotguns were more my thing.

Shooting from a bipod with a rear bag on a 58-62* sunny day with 0-5mph wind from the rear, the rifle has an 18" Rainier Match/SPR stainless barrel in a 1:8 twist and .223 Wylde chamber. Between each type of bullet, I ran a couple patches down the barrel otherwise no cleaning or relubing was done. One side note, I shot the 77gr TMKs last. I have chrono data because another handloader showed up with one after I'd fired the other rounds and insisted I use it. I need one....it's just added to list of "needs" but other stuff keeps taking priority

Sierra 77gr Tipped Match King
BC: .420 (Above 2400fps) OAL: 1.06"

Best grouping:
5 rounds
23.0gr Reloder 15
2643fps avg
.570" group (small vertical shift due to breathing :( )

5 rounds group
23.0gr Reloder 15
2651fps avg
.388" group

I think the variation came from OAL. One "batch" was right at 2.260", mag length, until I realized P-Mags will accommodate slightly longer rounds...2.265" or so. I loaded the 2nd batch of TMKs at 2.262" (still heard a healthy *Ccccruuuuunch" (yes, I spent a long time shooting/working up to this load and beyond without pressure issues). Problem was, I forgot to label which were longer afterwards, so either could have been the more accurate load.

Sierra 77gr Match King
BC: .362 (Between 2500-2999fps) OAL: .997"

5 round groups
23.0gr RE15
.523" avg

23.6gr RE15
.493" avg


Sierra 69gr Match King
BC: .305 (2200-2800fps) OAL: .895"

5 round groups
24.7gr RE15
.559" avg

My 16" Rainier Match barrel shot the 69gr SMKs over 24.1gr RE15 phenomenally well (I'd taken off the 3.5x ACOG and used a 4-16x for the test):
http://img.photobucket.com/albums/v74/DownSouthTAS/Mobile%20Uploads/image_zps8cqjqqd9.jpg
But of course the 18" barrel shot it like crap.

mustangfreek
14 November 2015, 01:11
I'm curious on these newish little boolits myself, when I get a minute I'll read more,

Only have/ tried reloader 15 with these?

alamo5000
14 November 2015, 04:38
Are you matching cases?

Meaning-- before you reload weigh your cases and find 10 or 20 that are close to the same weight and reload those with the same charge.

Otherwise, I would not think 1/2 inch groups or better is that bad of a deal. [:D]

Former11B
14 November 2015, 11:41
Just tried RE15 thus far. I do have some AR-Comp and CFE 223 but the RE15 works well for pretty much all the heavy bullets I use.

As far as matching cases, I use the same type of brass, like once or twice fired LC, which is what I used for the test