I have a 308 that I am shooting 150grn ballistic tips out of, it has a 26" barrel, the velocity is right at 3100fps. I am using 50grns of 748 which in my book shows as max, but it also shows it as a little less pressure load than some of the others. This is over 100fps faster than the book says.

What are you guys getting with max loads and 150grn bullets from a 308

It's times like this I get on my Quick load program and proudly proclaim sensibility. Actually quick load (at least my version) seems to think there must be "hot lots" of 748 out there. And maybe there was at one time. It thinks that load is too hot but agrees with your velocity and thinks you are pushing about 67,000 psi. However I have a 308 bar with a 20" barrel that loves 150's over 49 grains QC thinks that load is over 60,000 psi and should be doing about 2920 fps but it only does 2750 chronographed.
I guess the bottom line as I would "speculate" is there may have been some hotter lots of 748 out there at one time. That is almost too good of velocity to believe is within good pressure.
The other day I had some 168tsx's going 3330 (300 win mag)at 1.5 grains less than book max with re22.....my only belief is I have a "hot lot" of powder. I am backing down on that lot and found that book maxes of other powders got the more reasonable 3150 fps. (And I didn't really see pressure signs with that speed of 3330). I think the bottom line is I would be wary of that much speed even though the books say its ok....I think your chrono is telling you that you might be just beyond the edge of where you want to be.

Most books are using 22"bbls. for their .308. At 25fps avg. / inch, that seems about right.

Without evaluating the actual load with your own rifle and under your particular atmospheric conditions, no one can say for certain if it is truly in the red zone or not, but the numbers seem to indicate it is.

My favorite load for my 20" FP LE-2 is 46 grains of Re-15 under the 150 grain Nosler BT for right at 2800 fps. It does everything I ask of it, and I have never found it to be lacking in the velocity department.

the book says 2990 with that load from a 24" barrel, I do know that speed is a high pressure sign, but I am not getting any other ones, the primer looks far from flat, and no hard bolt lift etc. I also have the bullets seated pretty far out, infact they are at the limit of what can consistanty grab the bullet. my book says that load is 43000 cup, and lists loads clear up to 52000 cup. It would seem I am within limits here. I was just wondering how tempature stable this load would be??

With this additional info, it would indeed seem that your load is OK for that rifle.

A couple of years ago, I had a 26" .308, and while I don't have the data handy, I don't recall getting much more than 2975-3000 fps with 150 grainers. Then again, I didn't keep it long enough to experiment with all suitable powders, either.

I can't say I ever noticed temp. sensitivity with 748, and Texas' temps can run the gamut.

It's your gun and your face and eyes.

If it were mine I'd back up a long ways. I'm astonished that you are not seeing serious signs of pressure.

My Sierra says its 26" uni reciev gets 2900fps using 49.9 grains from its batch of 748. Is speed a pressure sign? You are almost at mag vels now. Do your primer pockets loosen up with repeated usages? Food for thought. Best-o-Luck

my info is from lyman, it lists a 24" barrel and shows the 50grn load as 2990fps. So my extra 2" of barrel ought to be good for something. It also shows the load as generating 43000 cup, and lists loads as high as 52000 cup for other powders. my bullets are seated way long, infact they will not even function in my cz 550 clip. I don't see the primer even starting to get flat on my fired loads. I sized and reprimed the brass, no issues with primer pockets. Usually you can see the primer beginning to flatten out once the load gets up there, I saw this with a 22-250 load, shooting it in a little warmer weather than when I worked it up. I think I am going to stay with this load, it also shoots .5" out of my cz 550 varmint. I think this goes to show if you want hotrod 308 loads with 150's W748 is the velocity king

Hey CC, I could be wrong, but I believe WW developed WW-748 especially for the release of the 308Win & 7.62 NATO. So, it should be about a perfect match for it.

Having looked through some recent Manuals, I do believe RL-15 is the Velocity King in the 308Win. Tried it myself and found it a bit more erratic as I approached a SAFE MAX than I prefer.

Just wanted to mention you really should not be thinking that there is any usable corelation between the Velocities shown in the Manuals with a specific Load, with the Velocity you see in your own barrel with that same Load. Too many variables between the Chamber/Bore dimensions and the Cartridge components they used and what you are using.

If you were using CHE or PRE to help determine your Pressure levels, you would be in a much better position to be happy about that Velocity.

Guessing that you do not use CHE/PRE, if you get "Loose Primer Seating" after 8 or so reloads, you might want to consider backing off the Load just a bit. But, if they are still snug, you are blessed with a Fast barrel - enjoy it.

Best of luck to you,

quote:

Originally posted by Hot Core:
Hey CC, I could be wrong, but I believe WW developed WW-748 especially for the release of the 308Win & 7.62 NATO. So, it should be about a perfect match for it.

Having looked through some recent Manuals, I do believe RL-15 is the Velocity King in the 308Win. Tried it myself and found it a bit more erratic as I approached a SAFE MAX than I prefer.

Just wanted to mention you really should not be thinking that there is any usable corelation between the Velocities shown in the Manuals with a specific Load, with the Velocity you see in your own barrel with that same Load. Too many variables between the Chamber/Bore dimensions and the Cartridge components they used and what you are using.

If you were using CHE or PRE to help determine your Pressure levels, you would be in a much better position to be happy about that Velocity.

Guessing that you do not use CHE/PRE, if you get "Loose Primer Seating" after 8 or so reloads, you might want to consider backing off the Load just a bit. But, if they are still snug, you are blessed with a Fast barrel - enjoy it.

Best of luck to you,

eveyone has also told me about RL 15, and how great it is for the 308, I do think its a great powder, but it appears to be a better match with bullets in the 165-168grn weight class, I believe its hard to beat its performance in those weight ranges. whereas with 150's and my load seems to indicate w748 can't be beat with 150grn class bullets, which I believe are the best match for the 308, once you start gettting into the 168 weights, trajectory suffers quite a bit. a 308 shooting 150's around 3000fps is a nice combo

I've used 748 and RL15 in my various 308's. RL15 is my favorite with all bullet weights and has the added benefit of being temp stable.

The latest Winchester loading booklet says 48.5 gr. of W-748 for 2865 FPS and 48,000 C.U.P. for pressure. Seems a bit wimpy to me. When cartridges like the .270 Win. and .300 Win. Mag. are loaded to the 55,000 C.U.P. level, cutting the .308 by 7,000 C.U.P. seems a bit of paranoia by company lawyers to me. Hell! 48,000 C.U.P. is what they load the 30-06 at and we all know that the 06 is not loaded to it's full potential. That, plus you do have a barrel 4" longer than most rifles in .308 Win.
Paul B.

quote:

Originally posted by vapodog:
It's your gun and your face and eyes.

If it were mine I'd back up a long ways. I'm astonished that you are not seeing serious signs of pressure.

Does anyone think a loads that doesn't flatten or crater primers, doesn't stretch pockets, doesn't stick cases, or recoil worse than other loads could be dangerous to the point of blowing your face off? I mean with similar temperatures, no bore obstructions, no slight overcharge...Nothing obviously wrong. Can a load that gives no pressure signs other than 3% more veloctity suddenly go KABOOM?

quote:

Originally posted by bja105:
...Can a load that gives no pressure signs other than 3% more veloctity suddenly go KABOOM?

Hey Jason, Not normally.

It would take:
1. A barrel obstruction.
2. A firearm that has suffered "Cumulative Metal Fatigue" from repetitive use with Over Loads.
3. A mechanical fault with the actual firearm, like the recent situation with the Sako's exploding and their management trying to keep it a secret.
---

What has most people concerned is the reported 3100fps in the 308Win with 150gr Bullets. No one is saying it isn't possible, but it is very unusual and above the Velocity most of us would expect for that combination.

Just want CC to be careful until he knows for sure he has a "Fast barrel".

I'd say you're fine. Your velocity isn't that far out of the book and there is a myriad of reason for your extra 100fps. barrel length being one of them. FWIW seating your bullets out will reduce pressure.
Only on a few occassions have I matched the book velocity even when matching barrel length, bullet, powder, primer, etc.