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Maybe....

First, take a look at the pics and graphs. The graph that goes with the pic is right under the target pic. The target pics show the actual hits, and the graphs show the accuracy and SD for each target. Each graph also show a dashed line at 1 MOA for accuracy, and another dashed line for an SD of 20.













Some details:
  • The powder is A2520
  • The cases are new Lapua
  • Primers are Federal GM205M
  • Charge increment is 0.4 gr
  • Five shots at each charge
Notice the charge range on the last two are different than the first by 0.2 gr. I saw some pressure signs at 25.2 gr so I backed all the charges down by 0.2 gr. A

Also, notice contrary to what we often see, the numbers and accuracy are better near the max charges.

What I'm trying to control my excitement about is the consistency - finally! I hope that is. I'm kinda having RA, range anxiety, wondering if I can get similar results with previously fired cases. All of the above were shot with new Lapua cases.

Speaking of Lapua, I'm losing about 40% of my Lapua and Sig cases due to primer pocket expansion. Some of that is likely due to the high charges I tend to run, but if that were the cause, then I should only see about 20% instead of 40% loses.

I have noticed that the highly thought of Lapua cases in .223 vary in weight a lot - more than Sig and more than Hornady. This, and some other things, make me think that the .223 cases don't get the same "attention" as the long range/precision calibers.

Anyway, today I shoot the same charges in Lapua cases that have been reload 4 times. I had to check every primer pocket and a couple were so loose, the primer almost fell out. In fact, one primer did fall out! :blink: So about half of my 4x Lapua cases got thrown out. :frown:
 

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Tangle, that's interesting about the Lapua cases. I have used quite a bit of Lapua brass for my .308 loads, but have yet to actually reload any (still working through the new stuff). I have to admit, I am not as scrupulous as you in that I do not weigh the cases.
 

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Tangle, that's interesting about the Lapua cases. I have used quite a bit of Lapua brass for my .308 loads, but have yet to actually reload any (still working through the new stuff). I have to admit, I am not as scrupulous as you in that I do not weigh the cases.
Hey, who you callin' scrupulous!!! :tongue:

I typically don't weigh cases either. I do from time to time when I see things I don't want to see. But, spot checks don't look good for 223 Lapua cases weight-wise, and I find far more primer pocket expansion in Lapua cases than any other.

I suspect .308 will get more attention to detail in manufacturing that the lowly 223. The 308 is a long range/precision caliber. The 223, I think, kinda falls in no man's land. It's not a good long range round, and most are tin can and minute of man applications, so I doubt manufacturers give too much attention to 223 brass. :frown:
 

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I’ve read that Lapua brass rates very high for consistency. Out of curiosity have you tried Norma brass? Since brass seems to be emerging as one of your red ‘x’s
 

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I am happy for you, Tangle. It is odd on the brass, as a point of curiosity.
Science does have its' own rewards!
Please don't take up golf. :rofl:
Do people weigh their balls?
(If you think this is double entendre, get your mind out of the gutter.)
 

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I’ve read that Lapua brass rates very high for consistency. Out of curiosity have you tried Norma brass? Since brass seems to be emerging as one of your red ‘x’s
Lapua brass does rate very high for consistency, but that's for the long range/precision calibers, 6 mm, 6.5 mm, etc. I wish I could remember where I read/saw it, but another guy was talking about the high variation in weight of 223 Lapua brass.
 

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The developers of the 6mm Mongoose stated that Lapua cases would require neck turning if used to make Mongoose case because the thicker walls in the shoulder area leave the neck diameter too big. They recommended Lake City brass. I don't have Lapua cases but found Nosler cases are close to the max neck diameter after converting.

The majority of the brass I'm using is either LC or FC, which by appearance seems to be either LC makes FC brass or visa versa. Both are crimped primers, but I'm okay with that as de-crimping is a one-time deal and I'm going to prep the pockets regardless. Then I have a few stray Win and Perfection cases mixed into the lot. Another batch of once-fired LC brass is on the way here.

I've got some cases where the primer pockets aren't "loose," but they sure ain't as tight as they once were. A few will likely be culled on the next firing.
 

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The surprise for me is the A2520 powder. Seems like it's not one of the favorite powders out there. I was watching Johnny's Reloading Bench and he tested all kinds of powders trying to find a MK 262 clone. Of all the powders, based on repeated performance, his pick was A2520, so I gave it a try.

I think the major changes I've made that's produced the above excellent accuracy and low numbers is a Odin Works 18" barrel. I went to 18" to duplicate "Johnny's" loads with 2520 and I used new Lapua brass, not sorted, and the A2520 powder.

I'm nervous as a cat in a room full of rocking chairs thinking about going to the range and shooting the same loads in the same gun but using Lapua 4x loaded cases, also not sorted :blink:
 
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I've never used Alliant powders in rifle loads. I've stuck with IMR for my .223 and .30-06 for years, mainly because they've done well and I don't want to buy powders I find I don't like and be stuck with them. Going to Hodgdon powder for the Mongoose was a bit of a stretch for me, but I've been pleased with how they meter and shoot--so far. With the Goose, most anything is a shot in the dark. Benchmark may be my next experiment. ".223" powders are not necessarily compatible with the 6mm Goose, even thought based on the same cases with close capacities. Something to keep me busy anyhow.

Hopefully your loads are up to expectations. Kind of a bummer to find what one thinks will be a decent load turns out to be crappy.
 

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"Reloading: I don't want you to get all excited yet, but.... "

Hah! Will if I want to.

Could Tangle be near the conclusion of his "Consistency Odyssey?"
 
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Nice! Hopefully that will be repeatable over the long term.
 
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"Reloading: I don't want you to get all excited yet, but.... "

Hah! Will if I want to.
It's my thread, so you can't get excited until I say it's ok to...:tongue:

...Could Tangle be near the conclusion of his "Consistency Odyssey?"
More likely another false hope :frown:
 
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Maybe....

First, take a look at the pics and graphs. The graph that goes with the pic is right under the target pic. The target pics show the actual hits, and the graphs show the accuracy and SD for each target. Each graph also show a dashed line at 1 MOA for accuracy, and another dashed line for an SD of 20.













Some details:
  • The powder is A2520
  • The cases are new Lapua
  • Primers are Federal GM205M
  • Charge increment is 0.4 gr
  • Five shots at each charge
Notice the charge range on the last two are different than the first by 0.2 gr. I saw some pressure signs at 25.2 gr so I backed all the charges down by 0.2 gr. A

Also, notice contrary to what we often see, the numbers and accuracy are better near the max charges.

What I'm trying to control my excitement about is the consistency - finally! I hope that is. I'm kinda having RA, range anxiety, wondering if I can get similar results with previously fired cases. All of the above were shot with new Lapua cases.

Speaking of Lapua, I'm losing about 40% of my Lapua and Sig cases due to primer pocket expansion. Some of that is likely due to the high charges I tend to run, but if that were the cause, then I should only see about 20% instead of 40% loses.

I have noticed that the highly thought of Lapua cases in .223 vary in weight a lot - more than Sig and more than Hornady. This, and some other things, make me think that the .223 cases don't get the same "attention" as the long range/precision calibers.

Anyway, today I shoot the same charges in Lapua cases that have been reload 4 times. I had to check every primer pocket and a couple were so loose, the primer almost fell out. In fact, one primer did fall out! :blink: So about half of my 4x Lapua cases got thrown out. :frown:
Losing so much brass so early to primer pocket expansion is a definite sign your pressures are running too high.
 

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Nice! Hopefully that will be repeatable over the long term.
Hmmm, I wonder if this means it already hasn't repeated??? :blink:

This morning:

Lapua cases reloaded 4x:



While the accuracy of the three groups from the left is impressive, it's opposite of the above three graphs. Then the two rightmost groups are larger whereas the same ones above are smaller.

Here are the numbers:



Notice the SD "curve" is distinctly different in this last session than the first three. What is the same is the middle group. It's not a distinct load because I had to "downsize" the charges by 0.2 gr. So in the first graph above, the middle dot/charge is 24.4 and all subsequent middle dots/groups are 24.2 gr.

At least that middle charge, be it 24.4 or 24.2 seems to have the least change in SD and accuracy.

It sure makes one wonder if the reloaded Lapua cases give different results than new Lapua cases.

Tomorrow, I'll try the same loads in Hornady cases and see what happens.

This afternoon I'll be shooting Black Hills MK 262 to compare it to these reloads.
 

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Losing so much brass so early to primer pocket expansion is a definite sign your pressures are running too high.
Seems like I'm losing more brass than I should, even if it is due to high pressures. I've very carefully watched for pressure signs and if I see something of concern, I terminate the test. But, pressure is about the only thing that could expand pockets. Hornady cases are NOT showing the same magnitude as the Lapua and Sig cases.

And I did run some pretty high pressures for a while, maybe I'm catching the invisible results now???
 
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I just received 208 cases I ordered for converting. I thought I ordered LC brass, but apparently I ordered mixed Military NATO 5.56 cases, which are WCC and TAA, which I found is Taiwanese made. I'm not a big fan of WCC brass. They stamp crimp the case mouths but that part is trimmed off during conversion. A plus was it came nicely polished. The primers popped out fairly easily, so now it's a weekend of de-crimping and pocket prepping, at least some of them anyhow. At least I saved a couple of bucks by ordering the mixed lot.
 

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Tomorrow, I'll try the same loads in Hornady cases and see what happens.

This afternoon I'll be shooting Black Hills MK 262 to compare it to these reloads.
Well? Don't start that carrot-dangling stuff with us.

You know where I have problems with brass? I seem to have problems getting them to fit into the shell holders with out binding. I measure some, supposed to be .378 wide at the rim diameter, and find them at that or .379-ish. That when they start binding. Most read .376-.375. I find it a bit hard to believe the shell holders are that tight in allowances. I wonder if that is a dimension that isn't monitored closely during manufacture.
 
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Well? Don't start that carrot-dangling stuff with us.

You know where I have problems with brass? I seem to have problems getting them to fit into the shell holders with out binding. I measure some, supposed to be .378 wide at the rim diameter, and find them at that or .379-ish. That when they start binding. Most read .376-.375. I find it a bit hard to believe the shell holders are that tight in allowances. I wonder if that is a dimension that isn't monitored closely during manufacture.
Strange you should mention that brass problem - I've had the same problem, but all of mine have been on reloaded cases. I have had a lot of Lapua cases act like that.

I get the impression you're seeing the problem with new cases???

When I started seeing this problem with my cases, I did notice that some shell holders worked a bit better than others. My RCBS and Hornady shell holders are tight; my Redding shell holder is more forgiving. I thing my problem is case compression is making the rim groove too tight - kinda like a slight collapse of the brass.

I'll get something posted about the Hornady, MK 262, and IMI 77 gr Match later, likely tomorrow sometime.
 
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