I have several questions, I'll try to separate them as to not confuse everyone!! 1-I reloaded 100 Military cases using data from Nosler book #6. #200 CCI primers with 44 Grs. of IMR 4064 and Hornady 150 gr. polymer tip boatail big game bullets. These were set to an OAL of 2.758 instead of the 2.810 described in the manual, this was done in order to use the canalure on the bullet and didn't give it a thought until I was getting ready to load some different bullets in the next group. At that point I realized the 150 gr bullets were seated .427 into the case and the 147 gr. FMJ boatail I was going to begin reloading would only be seated .320 into the case. I would think that this is a MAJOR difference in Pressure! I realize that I didn't use a Hornady book but the bullet is the same weight/shape/and has a polymer tip. Ques. A- After completing the 100 rounds I realized that I had used 15 Magnum primers (CCI #250) in lieu of the CCI #200 which I had used in the others. The problem is that I don't know which 15 they are. Do the magnum primers create a higher pressure? Ques.B- should I have any concerns about over pressure? Ques. C- Does any one have data for the 147gr. FMJ boatail using IMR 4064?
Reloading .308
- Thread starter RayB
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243winxb
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Military cases - What brand? Read "Preferred Brass " here > http://www.6mmbr.com/308Win.html The brass may put you closer to maximum then you were thinking, but at 44 gr of IMR 4064 should be OK, pressure wise, with all bullets & OAL. My guess.
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lightman
Member
I checked 3 different books. #1.=39.1 to 45.5 #2= 43 to 48 #3= 44 to 48. Magnum primers can raise the pressure a little but your load is under max and I would shoot them. Just learn from this and tune your loading pattern in the future. My favorite 308 load is 46.0 of 4064 and it is a compressed load in LC match brass and is too hot for many rifles.
A- After completing the 100 rounds I realized that I had used 15 Magnum primers (CCI #250) in lieu of the CCI #200 which I had used in the others. The problem is that I don't know which 15 they are. Do the magnum primers create a higher pressure?
Magnum primers always create more pressure than standard primers but not very much and it would only be problem with loads that were at the very top end of the load range. Your load is a hot load, QuickLoad ballistics software predicts that the chamber pressures will be around 58,000 to 59,000 PSI (with the SAAMI max being 62,000 PSI). Seating the bullet deeper than the recommended depth and the magnum primer will cause the pressures to be higher than normal. There is one other thing that makes the pressure higher than normal, the Hornady bullet. Quite a few of the Hornady bullet profiles will create higher pressures because they seat more of the bullet in to the case - even when the bullet is seated to the recommended depth.
B- should I have any concerns about over pressure?
I'd only be concerned if the rifle you are using is rated at lower pressures than the SAAMI max. An M1 Garand that's been converted to .308 might not be the best rifle to use that round in but a bolt action rifle should be fine. The only problem you might have is the cases themselves might take a beating and will have a shorter life span than normal, you will probably see head separations sooner than is normal.
C- Does any one have data for the 147gr. FMJ boatail using IMR 4064?
I'd recommend using a powder charge weight of 40 to 44 grains but I suspect that you would find the best load somewhere from 40 to 42 grains.
Magnum primers always create more pressure than standard primers but not very much and it would only be problem with loads that were at the very top end of the load range. Your load is a hot load, QuickLoad ballistics software predicts that the chamber pressures will be around 58,000 to 59,000 PSI (with the SAAMI max being 62,000 PSI). Seating the bullet deeper than the recommended depth and the magnum primer will cause the pressures to be higher than normal. There is one other thing that makes the pressure higher than normal, the Hornady bullet. Quite a few of the Hornady bullet profiles will create higher pressures because they seat more of the bullet in to the case - even when the bullet is seated to the recommended depth.
B- should I have any concerns about over pressure?
I'd only be concerned if the rifle you are using is rated at lower pressures than the SAAMI max. An M1 Garand that's been converted to .308 might not be the best rifle to use that round in but a bolt action rifle should be fine. The only problem you might have is the cases themselves might take a beating and will have a shorter life span than normal, you will probably see head separations sooner than is normal.
C- Does any one have data for the 147gr. FMJ boatail using IMR 4064?
I'd recommend using a powder charge weight of 40 to 44 grains but I suspect that you would find the best load somewhere from 40 to 42 grains.
You'll probably be fine. I wouldn't advise loading more than a few until I had a chance to fire some of them though.
My sources say 47.7 gr is a max load in Winchester brass and CCI LR primers in the test barrel they used with a MV of 2903 fps. Magnum primers and military brass will increase pressure and speed. 2900 fps should be considered a max load with that powder. You'll hit 2900 fps in those cases and primers with less than 47.7 gr of powder.
If you have access to a chronograph let it be your guide. If you are close to 2900 fps you are right at a max load. Over 2900 fps and you are over pressure. Even with magnum primers and military brass you'll probably be OK at 44 gr of powder. If you don't have access to a chronograph shoot a few and look for pressure signs. If none, you're probably OK. I still like a chronograph and this is a perfect example of why. It is possible to put together loads that are too hot in some combos of components and rifles while below listed max powder charges.
147 gr bullets are close enough to 150's to use the same data. I'd think they would be OK as well. But shoot a few and watch for pressure signs. If you had been working closer to a max load I'd be more concerned.
My sources say 47.7 gr is a max load in Winchester brass and CCI LR primers in the test barrel they used with a MV of 2903 fps. Magnum primers and military brass will increase pressure and speed. 2900 fps should be considered a max load with that powder. You'll hit 2900 fps in those cases and primers with less than 47.7 gr of powder.
If you have access to a chronograph let it be your guide. If you are close to 2900 fps you are right at a max load. Over 2900 fps and you are over pressure. Even with magnum primers and military brass you'll probably be OK at 44 gr of powder. If you don't have access to a chronograph shoot a few and look for pressure signs. If none, you're probably OK. I still like a chronograph and this is a perfect example of why. It is possible to put together loads that are too hot in some combos of components and rifles while below listed max powder charges.
147 gr bullets are close enough to 150's to use the same data. I'd think they would be OK as well. But shoot a few and watch for pressure signs. If you had been working closer to a max load I'd be more concerned.
W.E.G.
Member
You won't notice any difference in the rounds with the Magnum primers.
While it is widely repeated that Magnum primers raise pressures, the evidence to support such claims is spotty or absent.
From the documentation furnished with "Quickload"
http://www.6mmbr.com/quickload.html
While it is widely repeated that Magnum primers raise pressures, the evidence to support such claims is spotty or absent.
From the documentation furnished with "Quickload"
http://www.6mmbr.com/quickload.html
stubbicatt
Member
With a new or strange cartridge or propellant, or substituted primer or bullet, doesn't anybody take cases from the same lot, load one at starting load data, increase each subsequent load by .3 or .4 grains, until maximum book load data, and fire them in succession, examine for pressure signs, etc., anymore?
I think you need to be a little more specific about what that load was. 47.7gr of IMR 4064 under a 150gr Hornady SST Interlock (#30302) is going to produce pressures that will be well over the SAAMI max average pressure for a .308 Win (about 67,000 PSI vs. the SAAMI max of 62,000 PSI). As I mentioned before, Hornady bullets tend to produce higher pressures than other bullets of the same weight. On the other hand, 47.7gr of IMR 4064 under a 150gr Sierra Match King will produce pressures right at 62,000 PSI.
243winxb
Member
308 win.
[/URL][/IMG] click for larger view. Yes, If you would compare 130 gr to 150 gr bullets of the same type, using the same powder amount, pressure would be lower with the 130 gr bullet. You would need to be using the lower powder charge for the 150 gr bullet. Do not go below the starting loads .
The 147 to 150 gr weight makes very little difference. Pressure will be higher with a longer bullet bearing surface making contact with the rifling, thicker copper jackets, and non-lead core bullets. Example of different bearing surfaces in the .224" bullets.
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These posts come up all the time on this and other forums and most the time there are 100 posts saying yes or no on the load when the easy answer is never stated.
If one really cares to know the easy answer well here it is. Seating depth doesn't matter to a point, type of brass doesn't matter, type of primer doesn't matter heck type of bullet doesn't matter as long as you check a couple data sources for load information for the bullet weight you are using then work up your load from the lower end of the load data until you see pressure signs or velocity reading that tell you to stop.
It amazes me the number of questions that are posted about seating depth and amongst all the answers only rarely does someone state that the seating depth published in the reloading books was for the test rifle or test barrel and probably won't be what your rifle needs or likes so figure out what your rifle needs, work up a load and see if your rifle likes it. If not adjust seating depth and rework load. Sure there are shortcuts to take when working up loads which experienced reloaders use and with some experience and studying the novice should figure these out on there own.
Reloading isn't rocket science but it's not looking at a load book and picking out a charge weight then loading 100 rounds without ever firing a shot either. If you want to get right down to it reloading is educated trial and error with some luck thrown in the mix.
Glockula
Member
The NATO brass makes the most difference here. There is less case capacity in NATO bras by 1 to 1.5 grains and you have shortened the OAL albeit not a whole lot. I load my 147's at 43gr of 4064 with LC or WCC brass and CCI 200s. I would be cautious working up higher. That's me though. YMMV
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