Benchmark Powder for .308

[ReaperDriver]

Anybody use it? Thoughts on it. It says on the website that its optimum for 155 weight and lighter bullets. I'm primarily shooting 175s and 168s right now with good success, but eventually will delve into the 155 bullets soon, although my early tests with them have been marginal.

Benchmark is supposed to be even more consistant and temp insensitive than Varget. Is that jiving with reality?

 

[CTone03]

Re: Benchmark Powder for .308

I'm definitely interested in that answer as well. I love me some Benchmark for .223, and I want to play around with it for 308 too.

 

[JPaul]

Re: Benchmark Powder for .308

I will be loading some SMK 175s saturday with benchmark, hopefully i will get to send some through. The Hodgdon site has reloading data for the 175s with benchmark so it must be okay.

 

[deadly0311]

Re: Benchmark Powder for .308

I ran some Benchmark with 155 SMK Palmas and it shot ok. Its definitely worth a load development. It works well

 

[918v]

Re: Benchmark Powder for .308

42 grains under a 155 Amax in a virgin Win/BHA/Hornady case with WLR is very accurate.

 

[Jumper]

Re: Benchmark Powder for .308

918v - Whats the velocity?

 

[918v]

Re: Benchmark Powder for .308

I dunno yet.

 

[fusiachi]

Re: Benchmark Powder for .308

I came up with a 155 Scenar load for my 18" DPMS that works well. I'm away from my load book but 42 gr. and 2600 fps. are in the ballpark. I'm sure that they can be pushed harder but I was looking for something relatively easy on the gun that wouldn't be shot past 600 yards so I'm more than happy with it.

 

[Unsichtbar]

Re: Benchmark Powder for .308

OR wait till after the first of the year for the wonder powder IMR 8082 xbr powder which has a burn rate similar to 4895 an is " virtually no change in velocity at temperatures ranging from -40 degrees F to 165+ degrees F.", since you are shootin a 19" barrel

But I still thing you need to reshoot that OCW test with RL15 or varget but 6 with loads.

 

[hunterwarrior]

Re: Benchmark Powder for .308

My experiance is limited, but shoots well in these two firearms.

--

Remington VTR - 308 Win

150 gr Hornady FMJBT w/can
42.4 gr Benchmark
CCI BR Primer

temp 83

2776 fps Ave
18 SD
46 ES

--

18" Imbel barreled FAL - 308 Win

150 gr Hornady FMJBT w/can
42.4 gr Benchmark
CCI BR Primer

temp 85

2698 fps Ave
31 SD
88 ES

--

18" Imbel barreled FAL - 308 Win

temp 85

150 gr Hornady FMJBT w/can
42.7 gr Benchmark
CCI BR Primer

2747 fps Ave
24 SD
68 ES

--

18" Imbel barreled FAL - 308 Win

150 gr Hornady FMJBT w/can
43.0 gr Benchmark
CCI BR Primer

temp 85

2800 fps Ave
21 SD
53 ES

 

[magyarbetyar]

Re: Benchmark Powder for .308

Bullet weight is really dependent on your barrels twist not the powder. Just got done doing a ladder test for my rifle with Sierra 155 HPBT and Benchmark powder. Had 20 rounds loaded .3 of a grain apart. The first 12 rounds were frustrating as every othe bullet was high and low. I thought I would never find an accuracy node. However once I got to rounds 13 14 and 15 I found my node. For my rifle about 42.6 grains of benchmark pushing a 155 SHPBT was were the magic happened. My rifle is a AR-10 with a 24" and 1 in 11.25" twist barrel.

 

[gnfiter3]

Re: Benchmark Powder for .308

Mag. Think we have the same AR, assuming you're speaking Armalite, mine has a CM barrel. Now I smile cause I don't have to shoot the 14 rounds you already did. I'll just put that load in my data for future reference.

Powder is a real pain to get down my way, at least the ones that I have tried from members here. Benchmark came up as a recommendation,(I think from you) but I didn't find it when the search was on. Any success with a Benchmark load for 168's?

By the time I shoot a lb. (5 or 8lbs, forget it) can't find it locally, BLC-2 was classic of that. Switched from 52's to 69's in .223 cause all the powders were recommended for heaviers pills, and two of my 3 AR15's are 1:8 twist. Also, it seems, powders that shoot heavy .223's also work with 168's. RL-15, TAC, etc. Have about settles on TAC for what I shoot, but no weight over 1 lb available.

 

[magyarbetyar]

Re: Benchmark Powder for .308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gnfiter3</div><div class="ubbcode-body">Mag. Think we have the same AR, assuming you're speaking Armalite, mine has a CM barrel. Now I smile cause I don't have to shoot the 14 rounds you already did. I'll just put that load in my data for future reference.

Powder is a real pain to get down my way, at least the ones that I have tried from members here. Benchmark came up as a recommendation,(I think from you) but I didn't find it when the search was on. Any success with a Benchmark load for 168's?

By the time I shoot a lb. (5 or 8lbs, forget it) can't find it locally, BLC-2 was classic of that. Switched from 52's to 69's in .223 cause all the powders were recommended for heaviers pills, and two of my 3 AR15's are 1:8 twist. Also, it seems, powders that shoot heavy .223's also work with 168's. RL-15, TAC, etc. Have about settles on TAC for what I shoot, but no weight over 1 lb available. </div></div>

Hey gnifter ya mine is a real Armalite AR-10 w/ a 24" barrel w/ 11.25:1" twist rate. It does not like anything heavier than a 155grn bullet. Shoots the 168's like crap. Can't get it under 1" with the heavier stuff. HOWEVER!! with 155grn I have printed a dime sized group at 100yds so I know the rifle is capable.

I started with 38.7grns of Benchark all the way up to 44.4grns totaling 20 rnds. I was not able to shoot the last 2. I stopped due to rain and didn't want to corrupt my date with changing weather conditions.

My next batch looks like this:
OAL length measured with ogive caliper is at 3.178 (this is what factory Federal 155grn GMM ammo was lodded to)
All Federal Brass once fired
Winchester Primers
Sierra 155grn HPBT
Benchmark Powder

Six batches 5rnds each batch) starting at 41.4grns and ending with 43.1grns in .3grn incriments.

I'll post results once I get a chance to get to the range.

 

[Jerry R]

Re: Benchmark Powder for .308

Benchmark seems to be one of the best powders for bullets in the 150-155 range for my 308. For some reason, everyone insists on using Varget with the lighter bullets but my experience has been better results such as lower spreads, higher velocities and far better accuracy with Benchmark. Plus, the best part is that I've found I'm using anywhere between three and four grains less charge. Just my opinion but it's working very well for me so I won't be changing any time soon.
Another good powder for the same range of bullet weight is Winchesters 748, extremely clean burning with great velocities but not very temperature sensitive.

 

[gnfiter3]

Re: Benchmark Powder for .308

Mag:
As you have found what your gun likes, no point in changing it. Esp. if the powder is constantly available. For grins when and if you want to shoot 168's, 42.5 of IMR 4064. The load is in mid range from the manual, so there no chance of hurting the best darn AR-10 ever made. 43 grs. works in my 40X, so I full length all the brass and trikle .5 more for the bolt. I start to shoot through the existing hole after 5 rounds. One day, when I quit smoking, I may shoot through it after 3 rounds.(smile)

I have loaded some 130 hp's to try, but have not shot them yet. I started with Berger moly 168's and that's what I have used for years. Retail went to $50+ a hundred on them, so I ordered Nos. Comp. 168's from Mid-South. Saved a bundle on them compared to local retail. Those 155's are very popular, but I recall the ones for long range, as in F class are really expensive.

When the 4064 is gone, I want a powder that will flow through my 550. so I'm on the hunt.

I have no access to a range over 100yrs. w/o driving 4 hours north, so I load for 100 yrd accuracy. Also, a long range heavy load is a waste for me, and a stress the gun doesn't need.

TAC may be my go to after the 4064, but I will try some Benchmark before getting a big can, if I can find it.

Good shooting

 

[gnfiter3]

Re: Benchmark Powder for .308

Jerry,
If you're happy, go for it. Load development is interesting, but so time consuming. As someone said, I'd rather be shooting than loading. See, if Benchmark isn't great for 168's then I don't need to change powder until I order more tips. My AR likes the 168's but may well like a number of things in the right combination.

Also, my goal is one powder for everything that I load a lot of, 69's in .223 and the 168'. That way I'm not using that 550 in single press mode, as I must with 4064. Seems as if, given enough time, anything could be made to work, with the factors of the barrel figured in. I was surprised to hear an AR-10 didn't like 168's, but I bet the combination of 43.5 with it will change that. Tweak it and go.

And yes, Varget is the sh** here, but, not only is it hard to find, it can't be the only game in town. 748 has been around a long time pushing .308. I'm really just understanding the powder burn rate and bullet weight combinations. I use to just buy a powder and play with it until I got what I wanted.

After all these years, I'm seeing what a science reloading is. OCW, Ladder, Chrony's, measuring devices, Damn! BUT, The Hide is a great place to go to school.

MAC 1:10- Old Shooters Never Die, We just get...RELOADED.

 

[mavrick10_2000]

Re: Benchmark Powder for .308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Unsichtbar</div><div class="ubbcode-body">OR wait till after the first of the year for the wonder powder IMR 8082 xbr powder which has a burn rate similar to 4895 an is " virtually no change in velocity at temperatures ranging from -40 degrees F to 165+ degrees F.", since you are shootin a 19" barrel

But I still thing you need to reshoot that OCW test with RL15 or varget but 6 with loads. </div></div>

I bought 2 pounds of XBR last week, I would have bought a keg, but didn't want to make that much of a commitment yet. No need to wait until next year.

 

[Jumper]

Re: Benchmark Powder for .308

I have been burning through a 500 box of .308, 135gr SMK's using IMR4064, IMR4895 and today, Benchmark. I have been trying to get the velocity up to at least 3000fps and maybe 3100. My rifle is a CZ550 varmint with a 26"bbl. With 49.0 IMR4895, fed210 primers, FC cases and an OAL of 2.843" I hit about 3010fps. This is a slightly compressed load and accuracy is good; .5"@100/yds or slightly less. My primers are flat and above that charge weight I started to see an occasional ejector imprint in the case head. So, 3010fps with accuracy is the best I could get with IMR4895 and the 135SMK's.

I did the same workup with IMR4064 but I used FED215 MLR for primers. I ran out of case capacity at 47.7gr. At this charge accuracy was poor, 1.1"@100yds and velocity was 2928fps. Best accuracy came at 46.7gr turning in a .3", 3 shot group @2897fps.

Benchmark. There is no load data for the 135SMK for Benchmark or any other powder for that matter. Sierra Ballistics tech line said to use 150gr bullet data and add 1.5gr to the entire load range to use with the 135gr SMK. I shot a 3 shot group with some 130gr PSP's I had to foul the barrel loaded with 44gr: 2897fps! 45.1gr's went 2963; 45.4grs -2992fps; 45.7 - 2992fps (again); 46.0 - 3037fps; 46.3 - 3020fps. I stopped at 46.3gr. Accuracy was VERY good. the last 4 load weights went into .5 or less with 46.0gr shooting less than .3". Group sizes were measured center-to-center. At 46.3gr there was no signs of pressure. The primers were just starting to flatten. The cases looked better than the max load of IMR4895. I'll try and post some target pics...

 

[Jumper]

Re: Benchmark Powder for .308

http://i139.photobucket.com/albums/q295/1Jumper10/TgtGfx.jpg[/img]]Benchmark and 135SMK's

http://i139.photobucket.com/albums/q295/1Jumper10/targets4and5-2.jpg[/img]]Benchmark and 135SMK's 46.0gr and 46.3gr

http://i139.photobucket.com/albums/q295/1Jumper10/TgtGfxtargets123.jpg[/img]]IMR4064 and 135SMK's

 

[Jayne]

Re: Benchmark Powder for .308

I don't have chrono data for the loads I was using, but I do have some accuracy results for a couple of loads out of my M700 all at 100 yards off a bench.


All 3 round groups with 168gr SMKs, lapua or BHA brass.

39.5gr benchmark ---

0.689" average for 6 groups on 2/12/06
0.663" average for 6 groups on 2/12/06


40.0gr benchmark ---

0.638" average for 15 groups
0.627" average for 8 groups
0.470" average for 12 groups on 9/29/07
0.638" average for 11 groups on 10/27/07
0.531" average for 6 groups on 11/11/07


With 42gr Varget it shoots about .1" smaller on average. With 42.5gr IMR4895 it shoots about .1" larger on average. You'll have to trust me I'm not typing in all that data tonight.

Out of my new GAP M700, those same 40gr Benchmark rounds were averaging about 1", but I kinda haven't been to the range in 2009 so I blame the trigger nut and not the load or the rifle.

I've not done any real tweaking with these, I just found a round that shot OK and went at it. I just bought 16 pounds of Benchmark from PV, going to see what the new rifle likes so I've got a load ready for my first RO class. They'll get me shooting again!

 

[gnfiter3]

Re: Benchmark Powder for .308

Jumper, logging that IMR load to try with 130 Speer HP's. Have to be in the ballpark.

 

[Jayne]

Re: Benchmark Powder for .308

Shot some over a chrono today out of my GAP built M700 (different from the M700 my previous data was based on). Here are the speeds I got out of various charges.

Cases are random federal match once-fired, CCIBR2 primers, 168gr SMKs.

Factory ammo speeds today ---

168gr Federal - 2620, 2672, 2663
168gr Hornady TAP - 2677, 2679, 2689
168gr BHA - 2620, 2602, 2616

Benchmark at various load levels ---

39.4gr - 2534, 2485, 2524
39.7gr - chrono malfunction

40.0gr - 2540, 2484, 2487
40.3gr - XXXX, 2536, 2555
40.6gr - XXXX, 2582, 2592
40.9gr - 2597, 2641, 2600

The chrono was flaking out on me because I was drifting left (bi-pod hop between shots, I wasn't on the bench well). I think I'm going to go with 40.9gr for now, should put me at the low end of factory.

Ironically my average group for this testing and an assortment of 40.0gr loads I had was 0.652". Seems like I've found my accuracy limit. Time for some training.

 

[Bob L Swagger]

Re: Benchmark Powder for .308

tag

 

[Leaddog]

Re: Benchmark Powder for .308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hunterwarrior</div><div class="ubbcode-body">
2800 fps Ave
21 SD
53 ES
</div></div>

Those numbers are not very good for consistent accuracy, especially at long range. They can be made alot better at the reloading bench. You are looking for mid single digit SD's and ES in the very low teens.

You must chrono at least 20 rounds to really see what your load is doing.