.224 69gr HPBT: change in POI from .224 55gr SP


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capreppy
October 3, 2011, 11:58 AM
My AR (DPMS 24" 1-8 twist bull barrel) is zeroed at 100 for 55gr SP (loaded w/25gr H335).

I have several sets of loads I need to test for a Sierra 69gr HPBT. I normally use 8.5" x 11" sheets of paper that I print a target on. I use the PDF's found at www.targetz.com (I'm a cheap bastard, but these targets are pretty decent and only cost me the paper and toner). These also fit well into a binder and I can write all of the load information on the paper to store for future use.

I know there will be a difference in POI at 100yards, but how much? I'm trying to determine if I need to adjust the scope (up or down as needed) or if the POI will fit on the 8.5" x 11" paper, then I'll not worry about it. Once I find the right load for my rifle, then I'll be able to figure out scope adjustments.

Thanks in advance

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longdayjake
October 3, 2011, 12:21 PM
you are going to have to shoot it to figure it out. Some rifles will shoot higher and some lower. It just depends.

MtnCreek
October 3, 2011, 12:24 PM
I've seen little change in POI between .223 bullets @ 100yds. You'll probably find less than 0.5 moa between the two.

capreppy
October 3, 2011, 12:29 PM
.5 MOA is fine. I've got 3.5" to work with on either side of center. Just want to make sure that the bullet is ON the paper :D

Don't want to shoot it and then have to hunt for the hole if it didn't make the paper. I've only got 5 rounds for each set and don't want to lose one because it decided it didn't want to hit the side of a barn.

I guess I could pick up a box of 69gr ammo and figure out where that hits...didn't think about that.

rcmodel
October 3, 2011, 12:49 PM
Or you could tape four targets together and make a bigger target. :D

Seriously though, if you are perfectly zeroed at 100 yards with 55 grain bullets, I'd bet my lunch money the 69's will at least still be on a single sheet of typing paper.

rc

rsrocket1
October 3, 2011, 12:58 PM
I would load up 5 rounds of "throw away" 69g bullets and see if they make paper at 50 yards with your 55g scope setting. My .308 22" has a very "whippy" barrel and when I change loads, the groups move drastically. Strangely, they all keep about 1 moa, but the difference between 100g plinker rounds with Unique and 150g full house loads with Varget can be greater than 4" @ 100 yards.

The bullet drop difference will not be much, but the barrel harmonics can cause you to send a very tight group way off of the paper. Hopefully not, but don't be surprised.

nastynatesfish
October 3, 2011, 05:27 PM
id say probally about 2.5-3" of difference at 100. thats what i had when i went from 50-69gr pills. depends how you load your ammo though. if your just starting i dont assume you loaded them all max load so it could be more. i just use one of the top targets on my sheet though.

capreppy
October 3, 2011, 06:22 PM
I am definitely not loading max. The different sets are laddered from mid to near max. I did some research to see what "range" others where using and used that to discern what my start and max loads will be. Obviously checked against the manuals I have, but I also (given the cost of powder and bullets) didn't want to waste those rounds which were not likely suspects.

I'm hoping to run these tomorrow. Temperatures are still warm (88F is expected as they high) and winds light at 5 to 10.

243winxb
October 3, 2011, 07:56 PM
Yes, POI will fit on the 8.5" x 11" paper. The 69gr Sierra & 68gr Hornady & Win. 55gr fmjbt groups have been very close to each other for me. The 55gr hits a little higher than the match bullets using the same sight setting. Powders i am using are IMR 4198 & 4895, starting loads to near maximum print very close.

ZXD9
October 5, 2011, 02:08 PM
I don't change my scope settings when testing various loads at 100y. They're all close enough for testing.

cemjr
October 5, 2011, 04:01 PM
I'll let you know how they work for me , Today I'm getting the press set-up, I plan to load 500 sierra 69grain HPBT using Varget. To date, all my ammo has been 55gr and 62gr m855. 16" AR15/ leapold 1.5x5

chrome_austex
October 5, 2011, 08:00 PM
You should easily be on paper.

The only time my various grain weight 223 reloads would have not been on paper at 100y was when my electronic scale went tits-up and tricked me into shooting a very low velocity batch.

Most of the time I see <1.5" POI shift between different loads at 100y, but min loads typically hit low.

capreppy
October 5, 2011, 08:06 PM
Haven't had a chance to get out and shoot these. Work got in the way of playing hooky for a few hours.

I'm hoping I can get out early tomorrow morning before the winds pick up.

capreppy
October 8, 2011, 03:22 PM
Well I finally got out yesterday to shoot these.

The Nosler 60gr BTBT shot 1/4 lower and the 69gr SMKs shot 1/2 lower. Definitely on paper. I've got my Nosler 60gr BTBT charge. These things are damn accurate and was easily able to get less than 1/2 MOA regardless of the charge. My best group was .4 MOA.

The 69gr SMKs however weren't as good. Need to continue my search for the charge for my weapon. I tried 24.6 thru 25.4gr of Varget and my best group was just over 1" :(
Gonna try 24.0 & 24.2 to see if they do better. I'll also try 25.6 thru 26.0 (compressed load). 25.4 started to tighten up and may be I need just a tad more powder to wrap up my load development.

I am also considering the 77gr SMKs (I've got a 1-8 twist so it can handle them). My buddy tells me it is possible that my rifle just doesn't like the 69gr SMKs.

MtnCreek
October 8, 2011, 03:30 PM
Your rifle may not like the 69 gr SMK, but if I had to guess, I'd say the varget wants some more pressure. I would work it up till I hit book max or started exp’ing pressure issues. Then bring it back down by 0.1gr increments till groups open back up and compare notes to your work up vs the work down. Varget wants to be loaded hot. If you want a milder charge for range work, you may want to try IMR 4895 or 8208xbr.

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