on the 308 bandwagon with 215 advise

[mikebob]

i love the 308 and been seeing alot of shooters trying these. I had a few extra 215's left from 300wm loads and some varget so what the hell, looked in my berger manual and loaded up some bullets from 38.5 - 41gr in 1/2gr increments .010 off the lands 3.00 coal which happens to still fit in my clip and setup target at 100yrds. I still cant believe each one of the shots is 1/2gr higher than the previous. i didnt run into any heavy bolt at all. i guess what im asking is should i try to go higher or just stick with one of the 2 nodes here. primers look ok to me also. what are you 308 heavy bullets shooters opinions. top brass 38.5 in order down to 41

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[Darkker]

If you only ever use bolt lift, primer or case "signs" for pressure, you will be constantly shooting near 75,000psi. Chronographs are cheap, and very accurate pressure reporters.

No you shouldn't load higher. You didn't state velocity, but those loads mimick the 208gr data. Without knowing your powder burning rate compared to book data burning rates; absolutely not.

 

[mikebob]

i did chrony the loads the 41gr load 2576. I guess i should have went into great detail how i measured all cases before and after shooting for .0001 expansion as i find it shows up long before chrony speeds show up. they all measured the same, no tight bolt, no primers flat. i just thought i would ask the people who have experiece shooting these big pills in 308 if it would be worth it to move on past these 2 nodes. 41gr is 2 gr over listed max for the 210gr and since there is no load data in the manual for the 215 i figured it would be wise to ask them if this is on par or move on up since trhis is not max in my rifle. the 40.5 and 41 grain were identical and 38.5-39 hit ragged hole no since in trying to go higher if going to hit max in 1 or 2gr or 25-50 fps. but i guess instead of asking i should have just loaded more up and shot until i hit pressure signs,.

 

[Darkker]

Then what do you think "max pressure" means?

If you mean SAAMI max pressure, I thought the fact that you shooting a 215gr bullet FASTER than data for a 208gr, would have been obvious that it's over-pressure...

If you mean components not flying apart, consider what we know:
Brass stretching permanently, happens at its tensile strength, or yield. While no one lists alloy specs anymore, it's widely accepted that Hornady(one example) tests their brass to 125-ish% of SAAMI max. Olin alloy C260 was spec'd to have a tensile strength of 75,000-ish psi. That just so happens to correlate what I've seen in my testing of the 308 with a Pressure Trace; an actual pressure measurement tool, not a W.A.G.

SAAMI long ago sent very carefully calibrated copper crushers to its members, they used carefully constructed minimum spec universal receivers and barrels(just like in load manuals). Their highly trained technicians conducted the tests with reference lots of powder from SAAMI's storage. The results were that calibrated copper crushers aren't accurate above approximately 45,000 psi; and the various members reported pressure differences on the order of 20,000 psi.

But hey, a random guy who reloads with off the shelf powder, ignoring the warning about lot variations being as large as 10%. Can probably stare at an unknown alloy case, use his calipers or his highly skilled bolt opening hand, on a mass produced rifle with unknown chamber specs; and be more accurate at knowing pressures before things explode, than any SAAMI member is.

You want to know if "it is wise" to take an already over loaded cartridge and continue to over-pressure it. I said no, it was not.

Well you asked for opinions, I gave you one; but it wasn't what you wanted to hear. If you don't really want opinions, or better stated obvious facts pointed out to you; why did you ask the question?

 

[mikebob]

dude i know you want to let everyone on here know how smart you are but from every thing i have ever read, discussed with brass manufacturer,you can call them they will be happy to tell you this since they design and build it, FOR EXAMPLE HORNADY SINCE YOU BROUGHT THEM UP READ HORNADY 8TH EDITION MANUAL PAGE 23. its right in their manual to measure expansion and when it hits .0005 its max pressure. there are tools to read chamber pressures and i have used a few. and every one of them will tell you when you are starting to hit pressure case expansion is at .0002 and max is at .0005 except magnums which is not uncommon for .0006.

I am not shooting a 208gr amax bullet so my pressure, velocity, etc wont be the same.

a 215 berger bullet with a shorter bearing surface, jacket, a different design, will not have the same pressure spikes as a 208gr hornady bullet. with all your measuring equipment i thought you would know that.

in my 300wm i can shoot the 215 faster than the 210vld with slightly less powder charge. i hit max pressure with the 210 at 78 gr and i went to 78.5 with 215 and no pressure. it has a much shorter bearing surface. even shooting at node 76gr the 215 has more velocity than the 210 at 77.

hence me asking people who actually shoot the 215 since no data recorded in manual.

Do you think every member on here goes and buys a chamber pressure guage to figure up their loads. i remember talking with speer a few years ago about this very thing, i was told that they shoot their test until .0005 expansion and then backed down 6% and that is what is published in the manual

unless you shoot the 215 and have data on that bullet then you need not to respond

 

[mikebob]

Admin please close or delete thread this one is not useful for anyone

 

[valleyloader]

Mikebob,

I am interested in hearing what others may have to say on the 215s in the 308 as well. I am having mine rebarreled and I intend to shoot the heavy bullets.

 

[mikebob]

i am a believer after trying them, i would have never guessed at this much velocity with a 215 gr bullet in a 308. mine is a 26" 1-10 twist. i can seat the bullets to coal of 3.00 which is .010 off the lands and still fit in my clip. after the first couple of responses here i loaded up some more and reach pressure at 42.3 gr. i think i will work with the 40.5-41 gr load which hit same vertical. i leave my scope dialed to 4.1 most of the time with my 175gr load and forgot to 0 it out for test. i noticed on target they hit pretty darn close to 4.1 ele just slightly right. if you come across some info let me know

 

[bigngreen]

I run a longer coal and Lapua palma brass and 42.5 gr of varget runs me 2460 fps and is very mild, the top end is 46.5 at 2680 fps. The 215 is epic when pushing the range on the he 308, I'm really looking forward to trying the Berger 200.20x though, it may be better with an outstanding BC but being able to run more velocity I'm thinking it will be the perfect balance point but finding them in stock has proven futile!
I would say your getting close to pressure, I would grab the closest high node and enjoy a whole new way of looking at the 308!

 

[mikebob]

Thanks for the info

I was really worried about loading up to Max. I didn't know with the big pill if pressure would spike drastically from no pressure to overpressure . I hit pressure long before you're 46.5 probably because I can't seat them out that far. I I am maxed out any farther and I hit pressure so I'm going to stick with the 40.5 to 41. I am going to grab a different crony this time to make sure that that 2576 was right. It was right in par from the other velocities as working up. I still find it hard to believe coming out of the 308

I'm going to continue with this 215. If you find exceptional results with the 200 would you please let me know what you find.

 

[PGJPJ]

I'm curious why the interest in such a heavy bullet for the 308. Obviously the BC will be much higher, but aren't you giving up too much speed? Or is there an advantage waaaayyyy down range?

Just wondering. Looks like they are shooting very well!

 

[bigngreen]

If you run the ballistics with the 215 you still have a rainbow type arc BUT your windage is significantly better and your range really extends, I started shooting them to play with ballistics through transonic into sub sonic a long range and I have to shoot the lower speed to have it sub inside a mile, the low node I shot subs around 1600 yards and shoots incredible at those ranges.

 

[mikebob]

well after doing a little testing between 40.5 and 41 i settled on 40.7. took it out and shot at 825 yards using 2530 velocity. well after missing target twice i adjusted elevation down accordingly and smack. opened up shooter app again and did velocity correction with 825 yards and 27moa and it spit out 2410fps. So either my chrony is on the fritz or i read it wrong ( i was wearing safety glasses instead of my prescription so ?) i dont know if i will stick with these bullets if i can only reach 2410fps although it did pop that target way harder than the 175vld at 2745fps. it still right at 1000ft lbs of energy at 1000 yards so i may still load and shoot them with my 175vld. nice thing is both bullets zero at 100 yards elevation the same but have to move 1 click left on windage for 215 so that is awesome.

 

[Canadian Bushman]

Varget is probably the fastest powder that should be used for the 215 in a 308. A lot of guys use it because accuracy is usually very good. Most seem to get to the 2500-2550 range out of 28"+ barrels.

If you need more speed, a long throat and re17 or h4350 will usually do the trick. Ive had rifles that would push well into the 2600's with h4350 and 2700's with re17 ( max loads).

The best way for a modest man to measure a loads pressure is to mic the case web of a given shell before and after firing. Once a case's web grows .0005" or more you are pretty much at the max of that rifle. Saftey wise the 308 will experience .0006-.0007 case growth at SAAMI max pressures. The action will handle this just fine, but you will drop case life down to just a couple firings.

P.S. My current 215 load expands a case web .0003" per firing.