Benchmark powder in .308 win
- Thread starter Wendyj
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JeepHammer
Moderator
I'm having great luck with Benchmark.
It's not nearly as sensitive about primers, cases, ect as say, Varget.
I'm a little under where I want to be on velocity, but the accuracy is exactly what I'm looking for...
Working up slowly so I can keep the accuracy.
I'll trade a little velocity for accuracy any day...
It's not nearly as sensitive about primers, cases, ect as say, Varget.
I'm a little under where I want to be on velocity, but the accuracy is exactly what I'm looking for...
Working up slowly so I can keep the accuracy.
I'll trade a little velocity for accuracy any day...
Have you had any magic loads with a 308 or are you working on other calibers. I know at the range for myself Benchmark put Varget to shame as far as accuracy. My barrel didn't seem to get hot in five shot groups with benchmark but by three varget had it pretty warm. Just standard hunting barrel.
The reason for JeepHammer's lower velocity and your lack of heat is simply that Benchmark is a little faster burning than is usually loaded in .308 (about like IMR 3031, which is more often seen in the lower case capacity .30-30). With a maximum load that's around 10% lighter than the more usual powder choices for .308, you are putting less energy in the gun with each round. Fast powders also tend to produce higher ballistic efficiency, meaning that a higher percentage of the powder energy winds up as kinetic energy in the bullet, leaving less to heat the gun or blow out of the muzzle unused. The lower velocity presents less total friction with the bore, too. These all help with heat. The only cost is lower maximum velocity, which won't matter until you get to long range. Plenty of deer are taken with bullets at .30-30 velocities.
I have no idea what bullet you are using, so I can't say exactly about other loads. For target shooting, the Sierra 168 grain MatchKing at 2.800" COL, with a Federal 210M primer and 43.5 grains of IMR 4064 in a Federal case copies the original Federal Gold Medal Match load pretty exactly. Your particular component lots will be different, so you still have to work up to it from about two grains lower, even though it's not a maximum load.
I have no idea what bullet you are using, so I can't say exactly about other loads. For target shooting, the Sierra 168 grain MatchKing at 2.800" COL, with a Federal 210M primer and 43.5 grains of IMR 4064 in a Federal case copies the original Federal Gold Medal Match load pretty exactly. Your particular component lots will be different, so you still have to work up to it from about two grains lower, even though it's not a maximum load.
JeepHammer
Moderator
3 round groups can lie, I usually shoot 5 round groups with the .30,
10 round groups with .223
I reduced until accuracy started to suffer,
Then I start to load up, usually 10 Groups, then average both accuracy and velocity to see what the velocity spread is between all groups.
Benchmark is AMAZINGLY consistent in velocity,
Even with mixed cases and different standard primers.
It nice to have a consistent load that isn't super particular about case type, prep or primers,
I couldn't really tell the difference between new brass & bench prime,
And mixed/reloaded brass & common primers,
Which is REAL unusual!
The other thing I noticed, my ARs cycle smoother with Benchmark.
The action threw all the cases in about a 20" to 24" circle,
Not all over the place like Varget or Winchester,
It 'Seems' a little cleaner than Varget, and ther is a night an day difference compared to the Winchester.
I have 8 pounds of CFE 223 that I haven't cracked the seal on yet,
I'm still trying to find the limits on this Benchmark with my Hornady V-Max rounds.
Another up side, this stuff doesn't draw moisture easily, and goes through the Dillon charge bar powder dropped just fine.
I can leave unused in the powder dropped overnight without any signs of clumping, and it doesn't seem to effect accuracy either.
I've only loaded about 50 of the .308 rounds so far,
I shoot 178 Molly coated bullets, and like the AR,
I start low and work up,
So far it looks VERY promising for the .30 also.
10 round groups with .223
I reduced until accuracy started to suffer,
Then I start to load up, usually 10 Groups, then average both accuracy and velocity to see what the velocity spread is between all groups.
Benchmark is AMAZINGLY consistent in velocity,
Even with mixed cases and different standard primers.
It nice to have a consistent load that isn't super particular about case type, prep or primers,
I couldn't really tell the difference between new brass & bench prime,
And mixed/reloaded brass & common primers,
Which is REAL unusual!
The other thing I noticed, my ARs cycle smoother with Benchmark.
The action threw all the cases in about a 20" to 24" circle,
Not all over the place like Varget or Winchester,
It 'Seems' a little cleaner than Varget, and ther is a night an day difference compared to the Winchester.
I have 8 pounds of CFE 223 that I haven't cracked the seal on yet,
I'm still trying to find the limits on this Benchmark with my Hornady V-Max rounds.
Another up side, this stuff doesn't draw moisture easily, and goes through the Dillon charge bar powder dropped just fine.
I can leave unused in the powder dropped overnight without any signs of clumping, and it doesn't seem to effect accuracy either.
I've only loaded about 50 of the .308 rounds so far,
I shoot 178 Molly coated bullets, and like the AR,
I start low and work up,
So far it looks VERY promising for the .30 also.
I'm now loading for the 165 gr accubond. The groups in picture was supposed to be a 5 shot group but is only four. Had one couldn't get primer to go off on. I won't be cleaning resizing and putting back in cleaner after being deprived. The corn media took forever to get out of the flash hole. These groups are from Nosler 165 gr. bt. I am going in the middle load of the benchmark with 40 grains of powder with the accubond. Kind of confusing as Hodgdon gives one load but not for the bullet I'm using and Nosler another. Nosler doesn't show the benchmark poder so I'm using Hodgdon site.
603Country
New member
Because of getting media stuck in the flash holes, I've gone to tumbling prior to depriming. But, when that approach isn't possible, I use a small air compressor (and safety glasses) to clear the flash holes.
Jeep hammer. I've got a Smith M and P sport. I know it will shoot 223's ok. I've thought about scoping it and hunting some varmints mostly coyotes this summer before deer season. They are in abundance. What kind of bullets if any do you shoot to hunt with 223? Would give me something else to reload for. Appears 223 much cheaper to reload than 308.
Here's my Bushmaster Varmint. 24" 1-9 twist. A few of my insanely accurate loads :
52 SMK , W748 25.9gr .337" group @ 200 meters (all loaded to mag length)
52 SMK , Benchmark 25.5gr .677" group @ 200 meters
69 SMK , Benchmark , 23.5 gr , .474" group @ 200 meters
69 SMK , 8208XBR , 23.6gr , .530" group @ 200 meters
52 SMK , W748 25.9gr .337" group @ 200 meters (all loaded to mag length)
52 SMK , Benchmark 25.5gr .677" group @ 200 meters
69 SMK , Benchmark , 23.5 gr , .474" group @ 200 meters
69 SMK , 8208XBR , 23.6gr , .530" group @ 200 meters
JeepHammer
Moderator
I shoot Hornady V-max, either 55 or 60 grain.
This just might be the way I load or shoot,
I get 'Issues' with Barnes, hyper accurate, but for me a little picky about twist rate/velocity.
I find the V-max a littl more forgiving up to a point,
You can still spin the jackets off in a 1/7 twist between 3,250 & 3,000 FPS.
I went with a 1/8 twist and 5R rifling this time.
5 groove barrels are generally don't try to shere the jackets off and don't crush the bullet quite as bad, so I'm giving it a try and see if I can get a little more velocity without scattering bullets...
It worked for several other match shooters, I'm not breaking any new ground here.
My one cold bore shot kill rate is about 95% out to 500 yards,
Drops to about 75% past that, so I'm trying to extend that a little bit.
Usually, if its past 500 I break out the .308
Pushing just a hair past 2,800 FPS at the muzzle and zeroed at 600 it shoots pretty well out a littl past 1,000 yards reliably with 178 grain rounds.
An all around heavier rifle is easier to shoot past the 500 yard mark, and it delivers enough energy at the target to put down a coyote in one round.
When I shoot targets, I'll take those extra long shots,
I won't when I'm hunting, not even coyotes.
Besides, the optics are set up for point blank to 500 on the .223,
The optics on the .308 have 30 MOA built into the mount, so it shoots fine at long range, but I can't dope down enough for 100 yard shots anymore.
I could with 20 MOA mount, but of the 30
This just might be the way I load or shoot,
I get 'Issues' with Barnes, hyper accurate, but for me a little picky about twist rate/velocity.
I find the V-max a littl more forgiving up to a point,
You can still spin the jackets off in a 1/7 twist between 3,250 & 3,000 FPS.
I went with a 1/8 twist and 5R rifling this time.
5 groove barrels are generally don't try to shere the jackets off and don't crush the bullet quite as bad, so I'm giving it a try and see if I can get a little more velocity without scattering bullets...
It worked for several other match shooters, I'm not breaking any new ground here.
My one cold bore shot kill rate is about 95% out to 500 yards,
Drops to about 75% past that, so I'm trying to extend that a little bit.
Usually, if its past 500 I break out the .308
Pushing just a hair past 2,800 FPS at the muzzle and zeroed at 600 it shoots pretty well out a littl past 1,000 yards reliably with 178 grain rounds.
An all around heavier rifle is easier to shoot past the 500 yard mark, and it delivers enough energy at the target to put down a coyote in one round.
When I shoot targets, I'll take those extra long shots,
I won't when I'm hunting, not even coyotes.
Besides, the optics are set up for point blank to 500 on the .223,
The optics on the .308 have 30 MOA built into the mount, so it shoots fine at long range, but I can't dope down enough for 100 yard shots anymore.
I could with 20 MOA mount, but of the 30
JeepHammer
Moderator
I shot a lot of Win 748. Hot powder but I found it particular about primers,
And you NEVER want to expose it to outside air any longer than you have to.
My big issue is what to did to gas blocks/tubes/bolts,
Really dirty and hard to clean back out once it welded down.
Worth the cleaning for the groups it will shoot when you get everything else right!
My biggest problem is finding primer it REALLY likes,
And flash hole size seems to be important with it also.
Drilling every case isn't my idea of fun,
And for the longest I couldn't find ANY primers, and when you did find them, beggers can't be choosers...
That's why I'm giving Benchmark a good try, and CFE...
Both are supposed to be a lot less picky about every thing else and still give good accuracy.
And you NEVER want to expose it to outside air any longer than you have to.
My big issue is what to did to gas blocks/tubes/bolts,
Really dirty and hard to clean back out once it welded down.
Worth the cleaning for the groups it will shoot when you get everything else right!
My biggest problem is finding primer it REALLY likes,
And flash hole size seems to be important with it also.
Drilling every case isn't my idea of fun,
And for the longest I couldn't find ANY primers, and when you did find them, beggers can't be choosers...
That's why I'm giving Benchmark a good try, and CFE...
Both are supposed to be a lot less picky about every thing else and still give good accuracy.