DA Load Tooo hot I say.

[p246]

Took two of the boys out to shoot at 7 and 800 yards today. My 260 wasruning Great. 5 mils up, 6/10th left and I was ringing steel in the sweat spot. 223 700 p followed on nicely. Then A big 300 with a knight force and chassis made the plate shake and shank. All goood except the 98degree heat. Then It’s Roberts turn with his LMT AR10 suppresssed Rifle for a gas gulper it is awesome. But alas the load had not been fully vetted. 85clicks up 7 left me boy and fire, thump, bulletsgoes high, primer pops from brass. Houston we have a problem. Three more shots confirm with hot temps this load is for artic climates, as it chucks primers like they taste like an armpit. So we will start over, 2 weeks till match no pressure, 175smk, 44 grains Varget. minimum magazine OAL.

[RCS]

Some years ago, the local gun shop called me and asked if I could stop in and look at a customers AR-15. The rifle
would no long shoot, just kind of stopped firing.

I opened up the lower and it was filled-up with fired primers, the spent primers finally stopped the hammer from
striking the primers. Checked the headspace which was bad, rifle was put together from parts not factory

[JB White]

All goood except the 98degree heat.......Three more shots confirm with hot temps this load is for artic climates...

Comment from the peanut gallery;
Flip side of the coin. Decades ago I had 30-06 hunting loads (220 gr. reloads) exhibit high pressure signs when the temp dropped below 25 degrees F. Primers and bright rings. I put a few rounds inside my jacket for about 15 minutes to warm up and all went back to normal. Fired one of the rounds left out on the bench and I had bad signs again.
Waited for a springtime plinking session before I used up the rest of the batch. Didn't use that load data anymore. Just putting that out there for the heck of it.

[Allen]

I wonder if some of this may be from reloads where the primer pocket has been reamed out too much or the cases have been fired and reloaded several times each which could cause a loose primer pocket or at least loose for the pressure exerted by a normal charge.

[p246]

Some years ago, the local gun shop called me and asked if I could stop in and look at a customers AR-15. The rifle
would no long shoot, just kind of stopped firing.

I opened up the lower and it was filled-up with fired primers, the spent primers finally stopped the hammer from
striking the primers. Checked the headspace which was bad, rifle was put together from parts not factory

We got a batch of department ammo in that started blowing primers. We discovered it when a rifle wouldn’t work. Picked up some brass and saw blown primers. One had lodged itself by the disconnector and stopped everything.

In this case we kNew it was a newer load. One of the other guys was picking the brass up and looking at primers. (During load development he decided to use the top node, but it was only 75degrees.) Guy looking at brass told Robert about the first blown primer. We found it in the chamber. A few rounds later we blew another primer. We had also shot enough to determine his velocity was up and his trajectory was too flat. We knew we had a problem and switched back to an old load.

He was counting on a modern powder coping with temperature swings but it was just too hot a load for that gun in near 100 degree heat. Even modern powders marketed as being less temperature sensitive are not magic.

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Comment from the peanut gallery;
Flip side of the coin. Decades ago I had 30-06 hunting loads (220 gr. reloads) exhibit high pressure signs when the temp dropped below 25 degrees F. Primers and bright rings. I put a few rounds inside my jacket for about 15 minutes to warm up and all went back to normal. Fired one of the rounds left out on the bench and I had bad signs again.
Waited for a springtime plinking session before I used up the rest of the batch. Didn't use that load data anymore. Just putting that out there for the heck of it.

Hmm that’s weird. I’m keeping very accurate records and normally the colder it gets the velocity goes down as an average. What you describe is the opposite. However I’m only using Varget, Retumbo, and H4831 so who knows on a different powder. Interesting observation though.

[p246]

I wonder if some of this may be from reloads where the primer pocket has been reamed out too much or the cases have been fired and reloaded several times each which could cause a loose primer pocket or at least loose for the pressure exerted by a normal charge.

Couple old hats on this crew. The guy watching the brass due to a new load was calling out flat primers from the beginning and he had gained just shy of 100fps when I put the data in the drag curve based on the corrected hits. (So close estimate on velocity gain, Rifle is suppressed so I could not use magneto speed).The brass was once fired ( now second fired Federal so it was in, or should have been in good shape). With everything factored I think he was pushing the load and it bit us in the heat. This is the only semi auto gun running in a pack of bolt guns. We/he might have been trying to stretch it a little too far.

[Former Cav]

very interesting as I was shooting 175 SMK's with 45.0 grains of varget at 1000 yards. Never had a problem. I was using Remington NICKEL plated brass as it was easier to find in the grass in MN.
I never had a problem with heat and varget. and that includes going out to SO. Dak shooting prairie dogs and it was 100 to 110 on day.

[jon_norstog]

Thank you for putting this up, P246. I don't sweat this stuff too much, now that I'm shooting Krags and 45-70 BP pretty much exclusively. For me the big question is this: if I see something, can I hit it? With enough force to knock it down? Something = deer, elk,or whatever


jn

[p246]

Thank you for putting this up, P246. I don't sweat this stuff too much, now that I'm shooting Krags and 45-70 BP pretty much exclusively. For me the big question is this: if I see something, can I hit it? With enough force to knock it down? Something = deer, elk,or whatever


jn
Yep punching holes in paper and hunting are pretty different in my book. I like to hunt in the brush, mainly because thats where I’ve had my best luck. But I’ll shoot at paper or steel if I can see it. The problem with the long range game is it can turn into a money suck. At least now there are some very good factory rifles to be had. Now if good glass was just cheaper.

[p246]

very interesting as I was shooting 175 SMK's with 45.0 grains of varget at 1000 yards. Never had a problem. I was using Remington NICKEL plated brass as it was easier to find in the grass in MN.
I never had a problem with heat and varget. and that includes going out to SO. Dak shooting prairie dogs and it was 100 to 110 on day.

So he was loading Federal Match which weighs about 180 grains where Remington or Hornady weighs in the high 160s. Internal water capacity is lower in the Federal. He’s also using a can which creates back pressure. The LMT chamber is also tight when comparing fired brass. So I assume those three things along with 100 degree heat tipped the scale out of his favor. I also was surprised because we are shooting a 700P with the exact same load but Hornady Brass with no issues the day before. Just goes to show you each Rifle is its own animal.

[Sandpebble]

Been a very long time so maybe things are different but back in the day Federal brass was too soft.... especially in larger calibers. One hot load and primer pockets were loose .

Once fired Federal brass found at the range were left there ..... and we used a lot of Varget because it didn't seem to care about temps that much

[togor]

Federal brass is said to run on the soft side for primer pockets. I have some from some GMM boxes, but haven't done anything with them yet. Lake City is my go-to brand. In fact I have a box of 8mm loads from converted LC53 '06 brass. It appears I should have backed off another half grain or so on the pulled down kraut powder because the primers are flat and the extractions are hard. But the primers are still in there.

[p246]

Federal brass is said to run on the soft side for primer pockets. I have some from some GMM boxes, but haven't done anything with them yet. Lake City is my go-to brand. In fact I have a box of 8mm loads from converted LC53 '06 brass. It appears I should have backed off another half grain or so on the pulled down kraut powder because the primers are flat and the extractions are hard. But the primers are still in there.

Well theory all shot to hell. Went back out yesterday till rained out. Same gun ran 8 rounds but POI started walking up. We were shooting at 700 yards. 9th and 10th round blew primers so we stopped. Primers on round 1 through 3 showed a little pressure, 4 through 8 primers showed more. As gas gun gets hot it appears to cause issues. I’m going to pull some of his reloads to ensure he does not have a scale problem. 44 grains Varget a 71 degree should be good. We shoot this load in another 700P bolt gun with no issues, but I load them on a different scale. Head scratcher.

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I loaded up some Hornady and Remington Brass on my equipment. I also loaded some with 43.1grains Varget over a 168 grain SMK which is a pet load I like. We will see. I agree Federal is a little soft but another guy is running the 43.1 load and is on his 4th reload. Gas guns can be a pain when trying to push them.

[togor]

Well theory all shot to hell. Went back out yesterday till rained out. Same gun ran 8 rounds but POI started walking up. We were shooting at 700 yards. 9th and 10th round blew primers so we stopped. Primers on round 1 through 3 showed a little pressure, 4 through 8 primers showed more. As gas gun gets hot it appears to cause issues. I’m going to pull some of his reloads to ensure he does not have a scale problem. 44 grains Varget a 71 degree should be good. We shoot this load in another 700P bolt gun with no issues, but I load them on a different scale. Head scratcher.

- - - Updated - - -

I loaded up some Hornady and Remington Brass on my equipment. I also loaded some with 43.1grains Varget over a 168 grain SMK which is a pet load I like. We will see. I agree Federal is a little soft but another guy is running the 43.1 load and is on his 4th reload. Gas guns can be a pain when trying to push them.

Well I just got out my caliper and checked the case web on some FC and LC brass, once-fired, never trimmed. Pretty much the same web thickness and case volume on both, from what I can tell. I load 42.4gr of 4064 to push a 168gr SMK through a 11.25 twist barrel on a AR action. That shoots to nearly the same POI as Federal GMM 168 grain. To be honest, 44gr of Varget pushing a 175 gr bullet seems like a stout load to me.

[Former Cav]

POI as Federal GMM 168 grain. To be honest, 44gr of Varget pushing a 175 gr bullet seems like a stout load to me.
like he said in one of the posts above, a lot of it depends on the rifle.
My load of 45.0 grains, Standard Large Rifle Winchester Primer, R/P Nickel brass and 175 Sierra Match King MOLY coated. THis load was "compressed"
worked fine.

but I can tell you I had something similar happen to me many years ago while shooting prairie dogs with a 25-06
I had 90 grain bullets (LOUSY but that was all I could get my hands on) can't remember the exact load but he results were as follows.
SHoot 4 rounds, all is well with the world (had a 8-32 x 50 Burris Black Diamond scope with mil-dot reticle)
shoot the 5th round and ....what duh...where did it go..... did I blink or what? the rifle stock (a savage bolt gun with the fancy laminate stock and varmint barrel with muzzle brake would make a PING sound (there is no SPRING in the stock like an AR 1!)
So I had my friend shoot it.
4 rounds ....great
5th round.... a perfect "smoke ring" about 140 meters down range....the bullet exploded from centrifugal force.
SO.....Had Ice and soda and water in a cooler.
put the bullets in a sandwhich bag and on ICE.
8 rounds.... good
9th round....POOF.... same smoke ring....
very consistent.
I ended up shooting out that barrel in like 750 rounds... I had a custom 6.,5 x .284 barrel put on it. Much better selection of bullets.
If I remember correctly....25-06 bullets were like 75, 90, 117, and 120 grain was all that was available. NOT much choice. The 120's worked the best actually and did not explode.