I grabbed 50 pieces of federal 223 out of my bin of tumbled brass, sized and checked length. Will weigh tomorrow. Probably a bit much considering the groups I'm starting from, but might as well limit variation everywhere I can. Gonna separate all the other stamps a bit later.
5.56/.223 not grouping
- Thread starter hardheart
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Metal God
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The Tac data I can find with a 55gr bullet is maxed out at 25.6gr and thats Hornady 5.56 NATO data . Ramshot does not appear to have Tac in there 5.56 data with 55gr bullets
I think you are way over max charge
EDIT , my Sierra manual has tac at 26.3 max with there 55gr bullets . In 5.56 data
I think you are way over max charge
EDIT , my Sierra manual has tac at 26.3 max with there 55gr bullets . In 5.56 data
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Sitting by head stamp is good enough. Weight sorting doesn't help. Sorting by volume helps by such a small degree that I don't bother.
Lightly neck turning garbage brass helped more than anything. But it won't turn a dumpster fire into a hot dog roast.
AJC1
Member
Correct weight sorting is a waste but weigh and look for outliers over a grain.
Barrel twist as mentioned should quickly narrow down your bullet selection. Next biggest thing I’ve personally seen that have dramatic affect on shooting 223 is your crimp. You don’t need one. So don’t do it. It will hold just fine with out it. Oh I’m sure someone here will argue. I’ve shot many years , have been on state rifle teams, and have gone to camp perry several times. You don’t need to crimp a 223. In fact I’ve had to invest in the correct size neck expander because the resizing dies over size the necks.
AJC1
Member
This is how I shoot. I use a mandrel to get the tension I want, guage pins are a lot cheaper if your on a tight budget and own a bench grinder.
If it's the same lot #. He won't have that large of outliers.
It will at most shave less than a sixteenth of an inch at the range the OP is shooting.
I was chasing volume sorting and other garbage when I needed to learn to not cant the pistol grip.
I "knew" it couldn't be my shooting because I could still shoot my bolt guns as good as ever....
AJC1
Member
I'm always assuming worst case range pickups. If it's out of the same bag or even the same lot he's golden. My ppu experience opened my eyes a lot. It was 308 but I apply the lesson to everything.
I should mention again the results in the op were the only ones with the crimped rounds. I didn't even own that die until the day before I shot that. The other rounds were loaded without a crimp, but otherwise the same, and were doing over 3 inches at 50 yards through the same rifle and scope at the same range. I don't know how much effect the crimp die has, good or bad, because my efforts so far have been equally bad with or without it. I don't have to crimp to test these bullets further, just didn't want to imply the horrific inconsistency could somehow be solely be due to the fcd. Might be the case for others, but in mine the fcd didn't have anything worth screwing up.
Toprudder
Member
FWIW, I tested the effects of crimp on 223 an found that crimping almost doubled my group size. With no crimp, I could chamber rounds multiple times and not see any measurable bullet setback or jump, so I don’t bother crimping.
jebova2301
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I have to agree with this. For my hunting or precision rounds, there is no crimp involved. The only reason I do any crimp on my bulk blasting ammo/range fodder is because I run it through a progressive press with a Lyman M die that expands mouth just a tiny bit to aid in the bullet staying in place with a bullet feeder when the shellplate rotates to the seating die. The crimp is basically just enough to remove that tiny amount of expansion.
Wow. 100% the RMR FMJs are the issue. The Hornady 55 soft points did so much better.
Different range today, benches are old warped plywood affairs without height adjustments on the seats, so a fair bit less accommodating (but vets shoot free here, $25/day at the other place, which was the only open local for months). So I rested on the mag, using a yoga block under the baseplate. I shot at 40ish yards, since they had 36 marked and it was close to what I *should* have dialed in as near zero. My elevation was actually on for most of what I ran today.
I tried TAC with the Hornady rounds, just three weights to start, 25, 25.3, 25.6. Using a tape and not calipers, it went 15/16", 7/8", 13/16", so I may keep increasing charge weights further to see if it tightens up more.
I then tried the same bullets with H335, only 25 & 25.3 grains. 5/8" at 25, 1/2" at 25.3. I had read over and over online that 25.3 under 55 gr bullets was an accurate combo, and that seems to bear out. Considering the suboptimal shooting position, I can't complain.
I did one 3 rd group of the RMR FMJ with 25 gr of H335. Two inches and eleven sixteenths...
Different range today, benches are old warped plywood affairs without height adjustments on the seats, so a fair bit less accommodating (but vets shoot free here, $25/day at the other place, which was the only open local for months). So I rested on the mag, using a yoga block under the baseplate. I shot at 40ish yards, since they had 36 marked and it was close to what I *should* have dialed in as near zero. My elevation was actually on for most of what I ran today.
I tried TAC with the Hornady rounds, just three weights to start, 25, 25.3, 25.6. Using a tape and not calipers, it went 15/16", 7/8", 13/16", so I may keep increasing charge weights further to see if it tightens up more.
I then tried the same bullets with H335, only 25 & 25.3 grains. 5/8" at 25, 1/2" at 25.3. I had read over and over online that 25.3 under 55 gr bullets was an accurate combo, and that seems to bear out. Considering the suboptimal shooting position, I can't complain.
I did one 3 rd group of the RMR FMJ with 25 gr of H335. Two inches and eleven sixteenths...
Rocky Mountain Reloading. I'm not sure what the issue is, they have a great reputation and I also have their 124 gr multi purpose 9MM. If you look at the video AJC1 linked in post #9 the guy didn't like the performance of their 55 gr FMJ, but it was about 1.5 MOA when he tested. About 4 times better than what I'm getting.
Dudedog
Contributing Member
RMR sells various batches of .224 bullets.
Usually on any 55gr FMJs they have a note something like this
Something like that would lead me to believe they are not match grade bullets.......
Something I would just use for "blasting" ammo
Having said that not all 55gr FMJs are created equal
RMR makes excellent in house pistol bullets and I have had excellent results from their plated bullets (not in house) as well.
(the 9mm MPRs shoot really well for me and others...)
There are LOTS of happy RMR customers.
I have used various non FMJ .223 bullets from them some of which shot very well.
OP sorry the RMR 55grs didn't shoot better for you.
Usually on any 55gr FMJs they have a note something like this
Something like that would lead me to believe they are not match grade bullets.......
Something I would just use for "blasting" ammo
Having said that not all 55gr FMJs are created equal
Good leaves more bullets for the rest of us
RMR makes excellent in house pistol bullets and I have had excellent results from their plated bullets (not in house) as well.
(the 9mm MPRs shoot really well for me and others...)
There are LOTS of happy RMR customers.
I have used various non FMJ .223 bullets from them some of which shot very well.
OP sorry the RMR 55grs didn't shoot better for you.
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No biggie, I'm still going to work with them a bit more. I can drop the powder charge even further. I didn't want to stray too far from the charges I had used already, since I had also changed the bullet variable and done case sorting this time.
Now that I can see that at similar charges on the lower end of what I tried the SP is much more accurate, I will ramp down further with both bullets to see if the RMR can catch up at lower pressures. I doubt it, but it won't hurt to get more time on the range. Also going to take the SPs further into TAC 5.56 load data as well, since there was tiny improvement as I went up in charge weight. H335 shot quite a bit better for me today, so I want to see where I need to go to improve with TAC, up or down.
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