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 Min. & Max. load data for W748 and 55gr fmjbt?
Raven6  [Member]
6/13/2008 10:41:12 AM
I just started loading .223 and can only find max. load data of 26.2/26.3gr. for W748 and the 55gr. FMJBT. What is the min. load for this powder/bullet combo? I made a small batch using 25.5gr to be on the safe side to test. From other data I've seen using other bullet weights it looks like the min./max. powder charge spread for W748 is about 1.5grs. 25.5grs. puts me in the middle of min/max-- Your thoughts?
ma96782  [Team Member]
6/13/2008 1:18:27 PM
Some may say to start 10% down from max. Some may say to use the book's min. Whatever path you choose BE SAFE.......start low and work your way up.

SO.......how did you like your loads? Do, you think you want to go up some or down some or just leave it? Handloading is experimenting too.......as every firearm is different. You know....YMWV.

Aloha, Mark
endersgame  [Team Member]
6/13/2008 2:40:07 PM
I use 24.8 gr of W748 with LC brass and either CCI#41 or CCI 400 primers with the 55gr. FMJBT. It makes a good light target/plinking round that cycles just fine with both of my rifles and is easy on the brass. I have some sets of loads going up in powder charge but have not had time to test them yet.
Raven6  [Member]
6/13/2008 2:44:49 PM
Mark,


Thanks, but I haven't had a chance to test the rounds I've loaded so far. The problem is, I've searched everywhere and can't find a published min. charge weight for W748 and the 55gr. fmjbt. I'm assuming that the 25.5gr charge I'm using is still at least alittle over min. I don't have a chrono. and don't really want to work up to near max, I just want a recipe for some good, not to HOT, plinking ammo.



Endersgame,


Thanks!! Guess I'll see how well the 25.5gr charge cycles my 10.5" upper and maybe cut down to 25grs. if all goes well.
oldjack  [Team Member]
6/13/2008 2:46:49 PM
I'm using 26.2 grains of 748 with 60 grain HP flat base bullets. Fired in 3 different varminters with no signs of high pressure. I use the same load for 55 gr fmj and found it to be quite accurate in all my ar's! I also tried the same charge with 53 gr hp bullets and in my 1/7 twist barrel carbine the bullet vaporizes about 15 feet from the muzzle. In a 1/9 twist they shot fine. Always start at recommended charge and work up loads a tenth of a grain at a time, watch for signs of high pressure.
innocent_bystander  [Team Member]
6/13/2008 3:04:52 PM
748 is very temperature sensitive. When the powder gets hot pressures go way up.

Moderate loads left in the sun on a 90 degree day can cause all sorts of problems.

Be careful.
MRW  [Team Member]
6/13/2008 3:30:48 PM
I use 26.0 for general work, leaving room for temperature spike here in FL
rg1  [Member]
6/13/2008 11:26:12 PM
I've found the best combination for Win748 with 55fmj's between 25.9-26.4 grains. Somewhere in that range has always showed best accuracy in my AR's. I've shot Hornady, Winchester, and military surplus 55 fmj's with powder in that range without pressure signs and without high pressure in the heat of summer. Some sources list data higher and even above 27 grains but I know that is excessive especially in hot temperatures. My favorite load is 26.4 grains of 748, RP cases, RP 7 1/2 primers, using Hornady 55fmj's seated to 2.215".
Your load with 25.5 grains will cycle your AR fine but you can increase it a little for more velocity without having pressure problems. Check your load for accuracy as that's what you're looking for. You can work up from your charge and test for any accuracy improvements with charges up to 26.4 grains. Just note that most data sources test their data in 24-26" barreled rifles or test barrels so you won't get that velocity in a 16-20" barreled AR and probably in the area of 200-250fps less.
Just saw your info on using a 10.5" barrel. Velocity will be very low and my guess is approx. 2100fps and possibly 2200fps with the short barrel. For that rifle I suggest 25.9 grains and no need to go higher as cycling will be fine from your 25.5-25.9. I don't have a short barrel myself but have seen others with full auto short barrels that cycle like sewing machines in that range.
Raven6  [Member]
6/14/2008 9:13:54 AM
Guys,


Thanks very much for all your input!!! It's people like you who make this such a great site
ozarkgunrunner  [Member]
6/15/2008 12:53:43 AM
Hornady 7th Edition reloading manual

.223 Remington, 55 grain bullet, W748.

Minimum load - 22.7 grains, 2,800 fps

maximum load - 26.4 grains, 3,200 fps

test firearm: Remington 700, 26-inch barrel.
Raven6  [Member]
6/15/2008 10:17:44 AM
Ozark,

Thanks, didn't have access to the Hornady load data!!!!
rg1  [Member]
6/15/2008 6:23:58 PM
Hornady data is from a bolt rifle with a 26" barrel. While the loads are safe I think they are optimistic as far as velocities? Expect velocities from approx. 2500 to near 2900 fps in a 20" AR from their start to maximum using Win 748 powder.
pnwwildman  [Member]
6/16/2008 10:13:06 PM

Originally Posted By MRW:
I use 26.0 for general work, leaving room for temperature spike here in FL


+1 less the Florida part.

26.0 grains of W748 in LC brass, Win small rifle primers and any 55 Grain bullet has worked really well for me.

Accurate and reliable.
ma96782  [Team Member]
6/16/2008 11:17:44 PM
I use 26 gr. W748, 55 gr FMJBT, Fed sm rilfe primers, in whatever commercial .223 brass I happen to have. I don't usually have military brass, as I use to get the brass for free from the police dept (once fired).

Aloha, Mark
ozarkgunrunner  [Member]
6/20/2008 12:14:48 PM
In my 20-inch barreled A2, 25.5 grains of W748 gave an average of 2,863 fps with a 55 grain fmj bullet. Temperature: 93 degrees, ES: 36 fps, SD: 13 fps.

Out of a 24-inch barrel, average was 2,956 fps, temp: 93 degrees, ES: 14 fps, SD: 06 fps.
ma96782  [Team Member]
6/20/2008 1:45:51 PM

Originally Posted By Raven6:
Mark,

Thanks, but I haven't had a chance to test the rounds I've loaded so far. The problem is, I've searched everywhere and can't find a published min. charge weight for W748 and the 55gr. fmjbt. I'm assuming that the 25.5gr charge I'm using is still at least alittle over min. I don't have a chrono. and don't really want to work up to near max, I just want a recipe for some good, not to HOT, plinking ammo.



OK.......my Speer #10 Manual lists (with a Ruger Mini14).........W-W cases, 55 gr SPEER's Spitzer Bullet, W748, Min 26.6 gr (2913 mz. vel.), Max 28.5 gr (3126 mz. vel.), using magnum CCI #450 primers.
______________________________________________

Hey, some experimenting is part of handloading/re-loading. Don't expect to copy someone's load data and have the same results. And, whatever you find is right for you......IT'S RIGHT FOR YOU. YMWV.

Aloha, Mark