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Remington37
01-03-2017, 06:49 PM
Just picked up a new 26 inch 308 with 1 in 10 twist. What kind of velocity can I look for? Shooting M852LR clone loads. Rifle is a Savage 111 LA. Thanks and new to this board

s3silver
01-04-2017, 03:32 AM
How heavy of a projectile are you planning to use?

Congrats on the new rifle.

handirifle
01-04-2017, 06:21 PM
Well if you google that ammo, it looks like about 2550 is the average. You might get 2600, but they are more concerned with accuracy than velocity. The two do not always go hand in hand.

Remington37
01-04-2017, 10:39 PM
175 to 180grainers . Thought about cutting it back to 22-24 inch and add a brake

darkker
01-04-2017, 11:54 PM
1) What kind of velocity can I look for?
2) Shooting M852LR clone loads.


1) Death and taxes, otherwise there are no standards in life. How tight is your chamber? How tight are your bore and groove specs? What pressures are you going to run?
2) There is no M852LR. M852 is an old 168gr projectile load. M118LR fits with your 175-180gr statement however.
But you said a "clone load", which you can't do. If you matched the performance however, then you already have your answer on velocity; so not sure what you're question really is...???

If you are referencing the oft circulated Army TM43-0003-27, that reference is wrought with false info.
First is the fact that ONLY the reloader & Nosler uses canister-grade gunpowder. Non-canister or parent grade, gets spec'd certain specifics and pressure tested at each lot for fit in the specific order.
Next we have charge info. Weight is another handloader creation. Extruded powder is designed to have it's burning rate controlled by geometry. Thus gets tested and loaded by volume, Not weight. So any info stating a charge weight is incorrect, or only half understood.

The 308 really doesn't get penalized nor benefited much, by barrel length; another handloader notion.
Can you achieve 2600fps with a 175gr bullet, and be within SAAMI pressures? Likely, but that depends upon your rifle, powder lot, and load technique.
Remember that there is a very good, very real reason why all powder containers tell you that lot variations can be as large as 10%. Simply copying a charge weight and assuming otherwise is false, and potentially dangerous.

We've pressure tested loads of magic bullet claims, I can see pressure "signs", and conservative data claims.

Ultra-cool bullets aren't magic, they build the same pressure. No you can't judge pressure with ANY form of repeatable or SPECIFIC accuracy by measuring or stating blankly at brass and primers. No data isn't conservative, it's the 10% lot variation you ignored the warning for.
Book data comes from SAAMI minimum spec universal receivers and barrel dimensions, with nary a mention of lots tested. You have a looser mass produced rifle. If you meet or exceed book velocity regardless of charge, you met or exceeded SAAMI pressure.

If that doesn't bother you, fine enough. But make an informed decision.

handirifle
01-05-2017, 02:25 AM
Final answer I guess is never ask a question about velocity , jeez.

Remington37, if you don't have a book on reloading, get one and learn it. Use what they tell you and you'll be safe. Stick with the components they list or if changing roll back the charges and work back up. Plenty of books will give you velocities to expect.

Rob01
01-05-2017, 10:19 AM
I shoot Hornady 178 BTHP pushed by Varget through my 20" .308 and get 2695fps. When I had a 22" I was getting around 2730fps. With a 26" barrel you should easily get 2600fps. Use one of the typical .308 powders like Varget, 4895, 4064 etc. Just work up slow and be safe.

m12lrs
01-05-2017, 12:35 PM
I hate to see that clone comment. Why would any reloader want to clone anything. Now if you want to meet a specific performance criteria that is a different matter.

Every barrel is different. You have to find what it likes. Personally i have played around with a lot.of powders with the .308 and always wind up back with varget.

Don't really understand why everyone chases velocity and pushes things to the max either. If you have.a nice accurate load a a half or even a whole grain off max your drops might be a little greater but wear and tear on your brass and equipment will be a better return.

darkker
01-05-2017, 01:55 PM
Final answer I guess is never ask a question about velocity , jeez. Not sure why you are upset about it? His question is too generalized, and the ammo he asked about is confused. The ammo he is talking about(bullet weight, and LR designator) is M118LR, not M852. I gave some insight into the nature of why his question is unanswerable in a quick mannor. He is free to ignore it, or consider it as he pleases.

LoneWolf
01-05-2017, 02:10 PM
Actually M852 was loaded with the 168gr SMK, where as the M118LR is loaded with the 175gr SMK. You can go on to www.hodgdonreloading.com (http://www.hodgdonreloading.com) and get an idea of a velocity range you may be in. I would guess with the 168gr and 26" barrel you're a little over 2600fps. Just remember every rifle is different. You're going to get some responses that help and some that just complain about how you asked the question around here.

If you have any questions feel free to PM me or post them up. There's a lot of good guys around here that know what they're talking about.

mbohuntr
01-05-2017, 07:47 PM
Perhaps we can be more helpful if we knew what type of shooting you were looking to do, hunting, or target? Each has it's own velocity rules and preferences.
Factory or reloads
Reloading is very rewarding for improved accuracy, but has a steep learning curve to keep you safe.

hardnosestreetcop
02-06-2017, 01:54 PM
Remington37 If your speaking about the M852 which is a 168 Gr Match load, the factory loading are Black Hills @ 2650, HSM @ 2625 and Federal @ 2650. From a 26 inch barrel you could see a 40 FPS increase, keeping in mind there are a lot of variables that come into play like chamber, brass, primer, crimp.

WeldNFool
02-06-2017, 07:02 PM
Hornady 165 grain, American Whitetail clocked on the radar at 2730fps plus or minus but most were over 2700fps. My hand loads with 175 grain Sierra tipped match kings ranged from 2250 to 2450fps. I was working up some loads for testing. That's all I have as far as fps.

bearcatrp
02-06-2017, 11:39 PM
Out of my 24 inch barrel and using 178 ELD-X bullets, getting 2720 fps using 43.9 gr of varget with no issues.

Slowpoke Slim
02-07-2017, 09:26 AM
OP,

Sent you a PM.

I know you're new to the forums.

I can help you separate the wheat from the chaff.

Badger
02-13-2017, 12:00 PM
I just got a new 8lb of Ramshot TAC. I have been exclusively using Accurate A2520 for years for .308 but sometimes hard to find and expensive. The Ramshot powder burn rate chart shows TAC to be slightly faster burning that A2520 and H4895. Their load data sheet says max charge for TAC is 47.1g with 150g Hornady BT-FMJ giving 2957fps with a 24" 1-12" twist, Hornady cases, WIN WLR primers. So I loaded three batches: 45g, 46g, 46.8g, but I used LC new brass, CCI Large Rifle primers with the 150g Hornady BT-FMJ w/cannelure. I did not crimp though, never do. So Saturday I went to the range with my Savage 10FCP-SR 24" fluted barrel (in an MDT TAC21 chassis now) and chrono. 72 degrees, clear and dry. 40 feet elev. With 10 round batches I got averages of 2935fps, 3012fps and 3051 fps for the three charges. The last one made my bolt hard to extract the cases and blew the primer out of two cases, so I only shot 4 rounds, did not shoot the other 6, will pull them. I was surprised that I got higher velocity than the data sheet, hardly ever happens to me. And the 46g (well below the 47.1 max) was the most accurate. I hesitate to post my COAL as it's such a different factor for each chamber/barrel, but that was pretty standard 2.80 - 2.805.

OK, I also loaded three batches of Nosler Custom Comp 175g HPBT. The Ramshot TAC datasheet says max is 42.8 for a velocity of 2673. So I made three batches of 10, 41g, 42g, 42.6, started shooting with the 41g of course. I got 2565, 2647, 2672. No pressure signs that I could detect even with magnifying glass examining the cases. As always, each rifle is different, start out with lower charges. The 42g had the slightly tighter group of 10 (.69") with the 175g bullets.

hardnosestreetcop
02-13-2017, 12:41 PM
Bader: "46.8g, but I used LC new brass The last one made my bolt hard to extract the cases and blew the primer out"
There are a several of reasons you had hard extraction and blown primers.(1) you were using a faster burning powder (2) Your were using Lake City 308,. Brass which has a lower internal case capacity than say Winchester commercial brass (3) your were .59% from the max load. When using LC brass keep your max loads 1-2 grans under the max loading.

Badger
02-13-2017, 01:42 PM
Yes occifer will do! I have read that LC brass is "thicker" and has less volume capacity, makes sense, thank you.


Bader: "46.8g, but I used LC new brass The last one made my bolt hard to extract the cases and blew the primer out"
There are a several of reasons you had hard extraction and blown primers.(1) you were using a faster burning powder (2) Your were using Lake City 308,. Brass which has a lower internal case capacity than say Winchester commercial brass (3) your were .59% from the max load. When using LC brass keep your max loads 1-2 grans under the max loading.

hardnosestreetcop
02-13-2017, 06:39 PM
10-4, good luck

bdmhntr58
02-14-2017, 10:59 AM
Was going over this conversation as I just bought a 308 for hunting, and now am confused as you all seem to be in favor of velocity around 2500 to 2700fps and I just went out and bought several boxes of Hornaday SST 165gr that have a rating of 2840fps...is this going to damage my gun? Secondly is there someplace a person can sell their old brass? Thank you