Thread: Getting ES down with 223

Shall apply some graphite to the necks for the brushed cases too.

Round 2... 25.6gn Benchmark 2

Skipped the control group with virgin brass, as the first round showed very little difference between new and fireformed (all else being equal)... Plus I was feeling lazy.

Same Forster dies. Same scale. All cases FL sized, trimmed, and wax residue wiped off with a rag. Second set has the extra step of the necks getting a scrub with a nylon brush and a dip in some graphite.

Wiped
3237
3242
3196
3205
3199
3221
3250
3242
3231
ES 54, SD 20.4, AVG 3225

Wiped, scrubbed, graphite
3296
3291
3271
3314
3254
3301
3292
3310
3266
3278
ES 60, SD 19.6, AVG 3287

Interesting thing I note from this is the 62ft/s increase in average speed on the second batch. Not sure how to explain that. First thought was perhaps the powder was acting like moly coating on the bullets... But my understanding is that coating bullets alone will drop velocity which you then recoup (and more) by adding more powder... So there must be something else going on?? Without the 3254 shot, the numbers would be a fair bit better, but I don't think it's fair to exclude it.

Temperature difference perhaps?

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Similarly cold nights between outings. Slow rate of fire with a fan going to stop it getting too hot and rifle allowed to cool completely between strings.

This was the starline brass again.

Slight improvement there with the slower powder, so next up, I'll try BM8208. Might switch brass to PPU too.

It's a conundrum alright

I'd be interested to see if your SD numbers differ dramatically for other charge weights. Maybe do 5 shot strings at 24.0, 24.5. and 25.0 ?

And then of course different primers. Wish I had different primers to send you for testing, but I use Fed205M for 223 as well...

When I did something similar in 308 several years ago, I tested Fed 210M, CCI BR2, and RWS. The RWS just about halved SD compared to the others...

Yeah the primers can sure make a difference. I have 400's and 450's I can test. Maybe that'll be a bit further down the line. Take the most promising load from all this testing, then see what effect the three types of primers have.

... Unless someone can save me the time and knows that one particular type fixes everything in 223 like RWS did for you in 308

I have done workups before and failed to find any nodes where ES/SD tightened up considerably with these light bullets.

I've found the remington 7.5 primers work well. I can send you some of you like.

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Thanks for the offer. Let's put a pin in that. I'll do another one or two tests and the best load can go into a primer shootout.

Hey have you tried your loads in another rifle, or try someones else's known "good" loads in yours?? This might eliminate the rifle as a cause??

now that right there is a plurry good point.......

I think the consistency I get with the 69's demonstrates that there's no fault with the rifle. Had some new lapua brass to fireform so chucked together another quick load this evening (1c at the range) and got some good results...

FL sized. Necks wiped.
26.0gn Benchmark 8208
Federal primer
55gn Speer Gold Dot
2.300" COL

3274
3272
3273
3239 (I was giving about 1 min between shots and noted the barrel was a bit warm, so decided to wait 5mins between shots from hereon)
3279
3288
3284
3294
3286

If I blame 3239 on either barrel heat or the government, then the ES is 22 and the SD is 8.2. It's 55 and 16 included, but those other 8 are good enough to warrant further investigation.

So I think next step is to repeat that test with PPU and Starline/ADI to see if the numbers are significantly better or worse.

Whoohoo ! That's more like it.

With your ADI brass, is there any significant crimp on the primer pocket ? That could also potentially be a cause for inconsistent primer seat / ignition. I just use a neck/mouth champher tool to cut out any crimp in the primer pocket.

Be very interesting to see if these results are matched in your other brass

IVE got CCI & federal match primers if you need some to try.

@ebf I had some 5.56 ADI which had crimped pockets but I removed those and chopped them all down to make 300 blackout cases (where it's since been used to make some really consistent subsonic loads ).

The remaining ADI I have is the "proper" 223 headstamped stuff which isn't crimped.

Same load (55gn Gold Dot, 26gn 8208, 2.300") tried with different brass:

PPU (fireformed, annealed, FL sized, trimmed, uniformed)
3245
3265
3293
3268
3293
3282

Starline (same treatment)
3301
3337
3370
3329
3317
3322

Starline is lower capacity so the increase in speed was to be expected. Each group has an outlier. With PPU it was the 3245 cold bore shot. With starline, it was the odd 3370 shot in the middle of the string.

PPU: ES 48, SD 18.7, AVG 3274.
Minus outlier: ES 28, SD 13.3, AVG 3280

Starline: ES 69, SD 23.3, AVG 3329
Minus outlier: ES 36, SD 13.6, AVG 3321

Interesting how Lapua isn't performing that much better than PPU. Group sizes were comparable.

Also chrono'd some 300 blackout 110 VMax. Early stages of load dev, so not huge sample sizes. Starline brass and CCI 450's.

20gn AR2205 @ 2.100"
2335
2321
2344
2343
2362
ES 41, SD 14.9, AVG 2341

(next powder redacted because there's no load data whatsoever and it's a dangerously fast stuff. I want no responsibility of anyone trying the combo should it appear in some idiot's search results one day)
Secret sauce 2.050"
Xgn
2116
2119
2148 (case had a flattened primer and later on wouldn't fit into a shell holder so has been discarded)
ES 32, SD 17.7, AVG 2128

X+0.5gn
2169
2174
2180
ES 11, SD 5.5, AVG 2174

X+1gn
2216
2220
2226
ES 10, SD 5.0, AVG 2221

I find this interesting because Starline's 300 blackout and 223 brass is formed from the same basic case. With 300 blackout, right off the bat, I'm getting low double digit ES and single digit SD's (in an even smaller case nonetheless). With their 223, not so much...

I think next step is to do that primer shootout with 223.