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DJ_Skinny
08-11-11, 18:34
I know this isn't breaking news or anything, but I wanted to share my experience and give some info back to the community.

I noticed a couple of weeks back while shooting at the 100yd range that I wasn't getting very consistent groups with the 62gr Lake City reloads that I picked up from CheaperThanDirt. I couldn't remember having this problem with the 55gr Federal I had purchased prior to this, and I was worried it may have been a problem with the gun or barrel.

So, this past weekend I conducted a little experiment with the last bit of the 62gr and a couple mags worth of 55gr. I stole the targets from thecolter's awesome post here:

https://www.m4carbine.net/showthread.php?t=75940

I wanted to shoot at 25yds to make sure my zero was accurate and minimize the amount of error on my part (a potentially large portion of the problem :D).

Just for reference, a quick spec sheet on the rifle:
-Daniel Defense 1:7 16" upper with a DD 12.0FSP
-BCM BCG
-RRA 2-stage match trigger
-Aimpoint ML3
-POF lower with Magpul furniture

Here's what I got:
http://i199.photobucket.com/albums/aa53/vudu182/target_62gr.jpg
http://i199.photobucket.com/albums/aa53/vudu182/target_55gr.jpg

This is 30 rounds with each type of ammo. Clearly, my rifle loves the 55gr. I was a little surprised by the difference in accuracy between the two. I was under the (apparently wrong) impression that the 55gr and 62gr were not that different in terms of trajectory and response to barrel twist. Consider me enlightened. :haha:

I'd love to hear if others have had similar experiences or have any other input for this thread. Thanks!

-Mark
The Cat
08-11-11, 18:42
This belongs in a different section, but your results with the 55gr mirror mine.
bp7178
08-11-11, 18:47
Which 55gr Federal load was it? The 5.56 or .223?

It seems they are both shipping in the same black boxes with the eagle logo, one listing 5.56x45mm XM193 and the other .223 AE223.
MistWolf
08-11-11, 18:51
Every barrel is a law unto itself. While there are certain trends that can be seen when comparing from a large sample, two identical barrels can give radically different results. The only way to know for certain, as you've done here, is to shoot and see what happens
DJ_Skinny
08-11-11, 18:58
Which 55gr Federal load was it? The 5.56 or .223?

It seems they are both shipping in the same black boxes with the eagle logo, one listing 5.56x45mm XM193 and the other .223 AE223.

Sorry. Yes, it is the .223.

Mods, if this is in the wrong location please feel free to move it.
Jfkudla
08-11-11, 18:59
Wideners is running a deal on 55 gr. ammunition..1200 rounds for around 340 bucks shipped. Got a box under my bed.
Wiggity
08-11-11, 19:13
Thanks op! I had similar experience
goodoleboy
08-11-11, 20:43
I reloaded about 500 rounds of my own lake city brass with 62 gr. SS109 bullets to M855 specs. To be honest, I get better accuracy out of 55 gr. loads than I do the 62. I think a lot of it has to do with the steel penetrator/lead combination not being as well balanced as the lead core stuff. I just bought some 75 gr. match bullets to try next. Wish me better luck with them.
bp7178
08-11-11, 20:57
I reloaded about 500 rounds of my own lake city brass with 62 gr. SS109 bullets to M855 specs. To be honest, I get better accuracy out of 55 gr. loads than I do the 62. I think a lot of it has to do with the steel penetrator/lead combination not being as well balanced as the lead core stuff. I just bought some 75 gr. match bullets to try next. Wish me better luck with them.

I'm sure without a doubt the 75gr will give you MUCH better results.

The M855 was never know for its accuracy.
shootist~
08-11-11, 23:49
The SS109 bullet with steel insert is not a precision bullet (plus there is no telling who's bullet you ended up with).

If you are into BVAC ammo, the 64 grain SP, new manufactured (new LC brass), seems to shoot pretty well to mid-range or a little beyond.

An out of state buddy came in last week to (in part) to sight in his 18" "varmit" barreled A/R at distance - and he picked up the BVAC 64s somewhere along the way. I ran a group of 6 that went 1.25" at 100 yds, (the only group I put on paper). His gun + budget 1-4 optic and this ammo held decent accuracy to 500 Meters.

I ended up with all of his once fired LC brass :) , and a couple of enjoyable range trips.
DJ_Skinny
08-12-11, 00:59
^Thanks for the heads-up, shootist~. I'll give those a shot (um.. no pun intended?).
markm
08-12-11, 08:54
The IMI M855 performed pretty good for me. But yeah... the SS109 bullet isn't known for doing anything particularly well... especially accuracy.
Texas42
08-14-11, 08:33
There can be a lot of difference in fmj bullets. I got some from Graf's (left), but recently bought a bunch from a fellow who was getting out of reloading for a decent deal (right). All 55 grain fmj's
9380

9381

The "new" look nicer. I haven't been able to shoot them, yet. We'll see.
RogerinTPA
08-14-11, 10:32
Wideners is running a deal on 55 gr. ammunition..1200 rounds for around 340 bucks shipped. Got a box under my bed.

I bought 4 cases of that IMI ammo. I test a few mags last weekend and was very impressed with the accuracy out of my 14.5 DD light middy barrel with both iron sights and aimpoint t-1.
shootist~
08-14-11, 11:53
I bought 4 cases of that IMI ammo. I test a few mags last weekend and was very impressed with the accuracy out of my 14.5 DD light middy barrel with both iron sights and aimpoint t-1.

Same here with my 14.5" DD LW Middy; ~2 MOA from benched with a 4x magnified optic at 100 Yds. I also like that it shoots pretty flat with the shorter barrel.
Failure2Stop
08-15-11, 11:59
I think a lot of it has to do with the steel penetrator/lead combination not being as well balanced as the lead core stuff.

And BINGO was his name-o.