I had a question about .308 overpressure. I always load below specs. I loaded some 168 grain Barnes Match Burners for use in a PSA .308, with 44 grains of Vithavouri N-135 powder, and according to the specs this was one grain under max. Using Win. primers and IMI brass. Thought it would be fine. Went to the range, and not until ten rounds did I notice the primers came right out of their pockets, the case base was distorted so much I could not use them to reload and needless to say I stopped and pulled the rest. I wrote Vithivouri and they said their specs were for a bolt action 24 inch rifle with a flat based bullet, and a boat tail would produce drastically different pressures. Can anyone tell me what went on, in general, and what I can do to have this not happen again? Ever. LOL! I have read seven reloading manuals before, have reloaded for years, and nowhere did I ever read that the shape of the bullet itself would produce such a drastic difference. I did find that 39 grains showed no signs of overpressure, but I won't go any higher than that. Tom.
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Plugging 44gr of N135 into quickload with my brass and a 168 ELD-M I get over max and then some. Depending on what case volume I specify the pressure can hit 74K. I am thinking that IMI brass is more military in nature...very thick and lower volume. Is it compressing hard when you seat the bullet? Do you know what the case capacity is?
What you could do so this doesn't happen again is do a proper load work up.
https://www.vihtavuori.com/reloading-data/rifle-reloading/?cartridge=30
Max 39.8gr to 42.1gr
https://www.vihtavuori.com/reloading-data/rifle-reloading/?cartridge=30
Max 39.8gr to 42.1gr
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Max load for N135 varies from 39 to 42 on those charts. Is this because of the shape of the different bullets? I screwed up somewhere obviously, I'm just trying to figure out where. I load 5-10 thousandths under 2.800 because I have found that there are no magazine/feeding issues this way. Do you think it went so far beyond max. the rifle could have been damaged? Next shots I'm concerned about.
I’d definitely take a close look at the lugs especially on the bolt head.
44 just seems like a lot for that fast of powder and vihtavouri data confirmed
Did you chronograph the loads?
44 just seems like a lot for that fast of powder and vihtavouri data confirmed
Did you chronograph the loads?
Rifle definitely experienced strain however whether or not it was enough to cause permanent damage, no clue without personally inspecting parts. I would go over everything and look for stress fractures and/or damage, paying particular attention on the cam pin, bolt lugs, firing pin tip, extractor claw, ejector plunger, bolt body near the cam pin hole, upper receiver. Generally speaking (very generally), quality made parts in the 308 AR platform can survive a few popped primers. Should you expect an overall shortened life expectancy for your parts? Probably.
Those charts list 39-42 as a guideline because of bullet shape, bearing surface, and how it can affect pressures inside the bore of the barrel. Bearing surface is the contact area between the bullet and barrel. Some bullets have a longer bearing surface than other bullets, even if they have the same weight. Other factors such as individual firearm/barrel differences, seating depth, brass case capacity, so on and so forth can change what the max limit is.
Where you screwed up is basically your failure to do a proper load development for the individual firearm that you have. Every firearm is a little bit different but the differences can large enough to cause very different results when it comes to handloads. If you've been reloading for years, you've gotten this far by luck. Please do not take any of this as an insult but instead use this as an opportunity to refine your loading practices by going back to basics.
Check out the stickies in this part of the forum. Lots of great info.
https://www.snipershide.com/shooting/forums/sniper-s-hide-reloading-depot/
Those charts list 39-42 as a guideline because of bullet shape, bearing surface, and how it can affect pressures inside the bore of the barrel. Bearing surface is the contact area between the bullet and barrel. Some bullets have a longer bearing surface than other bullets, even if they have the same weight. Other factors such as individual firearm/barrel differences, seating depth, brass case capacity, so on and so forth can change what the max limit is.
Where you screwed up is basically your failure to do a proper load development for the individual firearm that you have. Every firearm is a little bit different but the differences can large enough to cause very different results when it comes to handloads. If you've been reloading for years, you've gotten this far by luck. Please do not take any of this as an insult but instead use this as an opportunity to refine your loading practices by going back to basics.
Check out the stickies in this part of the forum. Lots of great info.
https://www.snipershide.com/shooting/forums/sniper-s-hide-reloading-depot/
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If you are a new reloader and don't fully understand the impacts of coal/compression/bullet length, please please please don't start with max book load. Even at 42.0 you would be overpressure with say a 168gr full copper like a TTSX at 2.80.
38-39 would be a much safer start at 2.79-2.80 for Barnes Match burner.
Also just because I can run 44gr of N135 at 2.900 coal for a 168 weight bullet on my long throated Desert Tech barrel and still be below pressure with new Lapua brass - it can still absolutely be unsafe on your AR10 chamber with Hornady brass. Best case in point would be 223, in my DTA Rem match chamber, I can easily run an extra 2.5-3gr of varget over what I would run for a gaser because I load my 77 at 2.525" for my bolt gun chamber as opposed to 2.25" for a gasser. Freebore and powder compression can make huge differences in pressure.
Is you're rifle damaged ? hard to say if but it should be able to survive one blown primer and running numbers you were definitely hot (probably 65-70K but most likely not 80K/proof load hot)
38-39 would be a much safer start at 2.79-2.80 for Barnes Match burner.
Also just because I can run 44gr of N135 at 2.900 coal for a 168 weight bullet on my long throated Desert Tech barrel and still be below pressure with new Lapua brass - it can still absolutely be unsafe on your AR10 chamber with Hornady brass. Best case in point would be 223, in my DTA Rem match chamber, I can easily run an extra 2.5-3gr of varget over what I would run for a gaser because I load my 77 at 2.525" for my bolt gun chamber as opposed to 2.25" for a gasser. Freebore and powder compression can make huge differences in pressure.
Is you're rifle damaged ? hard to say if but it should be able to survive one blown primer and running numbers you were definitely hot (probably 65-70K but most likely not 80K/proof load hot)
What is the part number for the 168 grain Barnes Match Burner?
I looked on the Barnes Website and it isn’t listed?
Also, how many calibers have you reloaded for?
I'm entering your data in QuickLoads, and I'm at 70,400 psi
But it shows you're at a 114% fill ratio with 44 grains of V135
Did it sound like you were pushing your fist into a bowl of corn ships when you seated the bullet?
How did the seated bullet not get pushed out without a ton of neck tension? (which will add more pressure)
I looked on the Barnes Website and it isn’t listed?
Also, how many calibers have you reloaded for?
I'm entering your data in QuickLoads, and I'm at 70,400 psi
But it shows you're at a 114% fill ratio with 44 grains of V135
Did it sound like you were pushing your fist into a bowl of corn ships when you seated the bullet?
How did the seated bullet not get pushed out without a ton of neck tension? (which will add more pressure)
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Interesting, I can't find any 168 as well ... did the op load 175 gr bullets with 168 data ? cause that would definitively increase the pressure.
It certainly didn't look like the brass was anywhere near filled up. No crunching at all. I think what I may have done, is misread the loads for 135/150 and put 44 grains of 135 in instead of 150. I don't drink, I don't play the radio, and I don't focus on anything but reloading, and still that happened. And come to find out, they were 168 grain alright, 44 grains loaded powder, IMI brass, and COAL of 2.795, but Berger Hybrid Target. If you have any more info. on that round, please let me know as well.
No, not my first AR I have built/reloaded for at all. I made a mistake and didn't catch it. I don't drink, don't listen to the radio when I reload, and still this happened. They were Berger 168 grain hybrid target, and I think I accidentally loaded 44 grains of N-135 instead of using N-150. IMI brass, COAL of 2.795, and the primers popped right out. I caught it within ten rounds. Didn't feel that overloaded when shooting it, but feel is totally subjective. I reload for a dozen calibers. I think the biggest problem was downloading charts off the internet which printed out funny, so it was hard to determine the correct load, leading to a mistake without realizing it. I have since gotten a Vithavouri catalog/load book and it's much easier to use and decipher. I think I'll just use the clearer charts from now on. And I also think I used and old chart from Vithavouri which I have since found out, they used to publish their loads much hotter than they do now, having gone conservative after some problems. The max load on that chart was 45, so I started at 44. Now the max load for V-135 on my charts is 42. Three grains makes a huge difference apparently.
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Speer reloading manual #14 says “always begin with the minimum charge shown”.
And if I change any component besides the EXACT ones listed in the recipe I would recommend dropping 10% from the closest recipe you can find. THEN carefully work up in small increments.
Be safe, you only got 2 eyes and ten fingers. Preserve them.
And if I change any component besides the EXACT ones listed in the recipe I would recommend dropping 10% from the closest recipe you can find. THEN carefully work up in small increments.
Be safe, you only got 2 eyes and ten fingers. Preserve them.
berger 30425
Thanks. From now on, I will do exactly that. Yikes!
Ok, you said you’ve read seven reloading manuals.
And you reload for a dozen calibers.
And in your first post you entered the wrong bullet name brand and bullet name model in your post…
Sorry, but none of this adds up man…
And you reload for a dozen calibers.
And in your first post you entered the wrong bullet name brand and bullet name model in your post…
Sorry, but none of this adds up man…
Yep. I did all that. But I have since corrected my information.
Imi had the least average capacity of any brass i filled with water and weighted. It also averages in the 186 grain case weight with primer. 
So it’s very likely that you’re gonna run run the lowest charge weights with IMI 7.62 brass.
IMI(primed)
Black hills(de primed)
So it’s very likely that you’re gonna run run the lowest charge weights with IMI 7.62 brass.
IMI(primed)
Black hills(de primed)
So your 52.475 is just a little less than my CBC cases. Using that capacity with a 168 ELD-M loaded to 2.82 gets us 74,121 psi. But hey...you will hit 2674 fps from a 18" barrel! This guy was inventing the Sig .308 Fury.
QL also says this is a 119.8% load...how was it not spilling out the neck? 40.5 gr will get you 55,638 and should be more towards what you are aiming for...
Whew... i need to get QL.
I tried picking up the free one I’ve seen bouncing around the form but they didn’t have one for Mac don’t have a PC.
You can easily install a Windows VM on Mac via VMware parallels or other
I have since corrected the figures/information to having loaded 44 grains of V 135 I weighed it before and after when I was pulling, and it was the same. 168 grain Berger Hybrid Target bullets, IMI cases, COAL 2.795, Win large rifle primers, light crimp. Is the 74K estimate of pressure accurate for that bullet and load? And as far as case loading, it was nowhere near 100%, more like there was room below the neck even. If it had been that full, I would not have loaded. But it all seemed normal. The primers popped and I didn't notice at first because I was shooting a forward eject rifle, and it took ten shots before one came out. I stopped immediately. Thanks for the previous info. Everything helps. I just wanted to know what the pressure estimate was, because if it was below proof, then the rifle is probably fine? Thanks again.
The problem with running a quickload estimate is that at that point, it’s much more dependant on case capacity.
At 54gr H20 You’d be at 65k PSI
at 52.5gr h20 you’d be at 75k psi.
Which is a pretty big difference.
But again, assuming a colder temperatures it could drop an extra 5k psi if it was as cold as 20F.
44grains is way too much.
The manufacture doesn’t have data with that powder for that bullet.
Comparing to the Amax which does have N-135 data they suggest max charge of 39.8. If you notice the amax #’S and compare to same powders compared to the Berger Hybrid.
I understand you were just looking for the pressure numbers... be careful!!! As it sounds like you were somewhere in the neighborhood of 4 grains over charged.
Yeah none of this makes any sense at all. OP just loaded up 44gr of V130 and said "let's try this out"?????
I was taught to always start at 10%below max for your powder AND Bullet and check pressure. Then do load work up. Now way someone who's experienced in loading did that.
OMFG
Where do idiots like this come from?
IDGAF how long you've been reloading and how many manuals you've read. You clearly did not understand most of it.
Did you notice that you used a powder that VV does not list for your bullet, and even then you went FIVE grains over book max for a different bullet?
Do you understand what you're being told about the effects of case interior volume on chamber pressure?
You haven't hurt or killed yourself or others by sheer luck. I would stop reloading everything if I were you.
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No, he does not understand.
The red flag for me was that he did not understand about how bullet seating depth, and powder compression affected loads.
If he truly read seven reloading manuals, there’s no way he missed those parts.
The red flag for me was that he did not understand about how bullet seating depth, and powder compression affected loads.
If he truly read seven reloading manuals, there’s no way he missed those parts.
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Groundhog day
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