223 55g FMJ with Win 748?


February 26, 2010, 06:50 PM
I have been playing around with Win 748 and 55g FMJ's, and was wondering what experience other people had with this combo. With 25.5g, I am getting 2825 fps out of a 16 inch AR carbine, and it is running very smooth and consistent.

Does anyone else use a simliar load with 748? I would appreciate your comments.

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February 26, 2010, 07:57 PM

February 26, 2010, 08:19 PM
I stoked mine a bit more to get 3015 fps avg from an IMI Galil ARM w/18" barrel.

February 26, 2010, 08:29 PM
How much 748 did you use? I am using a 16" barrel, so I would expect a little lower velocity than your 18".

February 26, 2010, 09:23 PM
I'll PM you.

February 26, 2010, 10:07 PM
I've loaded Win 748 with different 55fmj's in most case brands from 25.9 up to 26.4 with 26.4 giving best accuracy with Hornady 55 fmj's. Your load if it meets your accuracy goal is fine. You can go up in charge and be safe but I don't recommend going over 26.5 grains. Just my opinion.

February 26, 2010, 10:17 PM
I am using LC military brass... is it safe to go to 26.5 g with military brass?

February 27, 2010, 12:51 PM
I have shot almost nothing but 55/26.0 WW748 in GI brass for about 40 years now.

It is a great load that works 100% in every gun I have ever shot it in.
Also very accurate in every gun I have shot it in when you use V-Max or Ballistic-Tip bullets.
Not so accurete with 55 FMJ-BT, but thats the crummy bullets, not the load.


February 27, 2010, 02:07 PM
With Mil-spec brass, you can go as high as 27.0gr. With commercial .223 brass you can go as high as 27.5gr.

I can get 3,000fps with 18.5" bbl.
Accuracy is usually as good as bullet and rifle is capable of. I use 26.9 (what the measure thows) and either a Nosler 55gr Ballistic Tip, or Sierra 55gr Spt to find out what a rifle is capable of.
I've got a Bushmaster ltwt bbl sporter barrel that will shoot under 1moa, and a Remington M7 that will approach 0.5moa on demand.....
I prefer Federal Primers, but I'm using up some CCI SRM that a friend left me when he passed away.... Still have serveral thousand......
It's the bullet and the barrel that are the variables in this equation...

February 27, 2010, 08:00 PM
I like rcmodels recommendation and will second it. I loaded 25.5 in LC Brass for a while, a little on the low side. I did have some short stroke issued in one of my rifles. I went as high as 26.2 without any issues. 26 was the sweet spot it seems. I really like the way the 748 runs through the powder thrower. I now use 3031 just because I ran into a large lot of it for $5 a pound. Works well also but takes more time, trickle charge and all. Bill

February 28, 2010, 12:02 AM
Whitey, i used a lot of 3031 but changed to 748 when i bought a thrower... at $5 bucks i would be happy to just trickle to top up.... nice deal....

Rc, i to like and use that load but with the cold winters in my area i use a mag primer.

Maj Dad
February 28, 2010, 11:03 AM
I've gone up to 27.5 and come back to ~26, 26.5 - it functions 100% of the time in mine, is reasonably accurate & easy on brass. On the other hand, though I don't load it a lot, I got better accuracy out of 25.5 gr of its cousin H335, all of these loads in a chrome-moly 16" 1-9 bbl.

February 28, 2010, 02:59 PM
RC, I am curious as to the primer you are using and whether you feel they make a difference in accuracy in you load.


February 28, 2010, 03:08 PM
I'm using close to the same for my "plinking ammo".

I don't have a chrono......sorry.

Function is 100%

February 28, 2010, 03:42 PM
I have never used any primer except CCI or Winchester Sm. Rifle and WW748.

My CZ-527 is a one-holer, and my AR-15 is sub MOA with plastic-Tip varmint, or HP match bullets.

I doubt changing primers will have anything to do with any better accuracy then I am already getting. So I never tried it.



February 28, 2010, 04:28 PM
I doubt it either. During the last primer shortage when we couldn't get any more 205M primers, many Benchresters went to WSR primers. Some said they were no going back to the 205M.

1911 Nut
February 28, 2010, 05:17 PM
I have used Winchester 748 powder with a Remington 55 grain FMJ bullet in my Colt AR15 HBAR with a 20" barrel with very good accuracy and 100% reliability. The chronographed MV is 3242 FPS with a very low sd of 13 FPS.

Factory PMC and Factory Wichester USA 55 grain FMJ ammunition both chronograph exactly 3234 FPS with slightly higher sd's from the same rifle, and the chronograph tests were done on the same day as my reloads.

But my loads were more thatn 25.5 grains. The top load in the Speer #11 Manual (one of the older manuals with the 4th printing in 1991) shows 28.5 grains of Winchester 748 as a top load in a .223 with a 55 FMJ bullet.

I used the same load (except the bullet was a Hornady 55 grain V-Max) in a Thompson Center Contender with an SSK Custom Shilen 15" barrel and achieved excllent accuracy, but the primers were significantly flattened when fired in the Contender. Primer pockets were not loose, brass was not cracked, and case head expansion was not abnormal, but the flattened primers caused me to back off to between 25.5 and 26.5 grains of Winchester 748 under any 55 grain bullet in that handgun as I worked to further develop loads.

I had normal appearing primers and no other pressure signs when the hotter load was fired in the Colt HBAR.

Hope this information helps.

March 1, 2010, 09:47 AM
The difference in published data through the years for Win748/BLC2 is simply due to lot-to-lot variations.

I've seen similar variation in HP38/Win231 also. Both are my "GO-TOO" powders for their respective cartridges/uses.

Lately, the BLC2 and 748 tend to be on the fast side of the range for these powders. Hence, the lower charges being reported....
Hence, we should always use current data....

I've seen Accruate #5 change three times... different manufacturers. Has made me leery of using Accurate powders ever since I worked up a marvelously accurate 147gr load in a 9mm target pistol. When I got another 5lb keg, powder was totally different and wouldn't hit the side of a barn. Ended up giving that keg away......

So, beware of any older data.......

March 1, 2010, 01:23 PM
Does anyone else use a simliar load with 748? I would appreciate your comments.Hey if it works good for you that all that matters.

Prefer H335 AKA WC844 myself, for bulk loading the 223 AR 52 - 62 grain bullets. Seems like I get better accuracy out of it in general. Been mostly using it in the AR since the 1980s when Hodgdon used to sell cans of H335 that had "surplus powder" below the H335.

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