55g .223 in 7” twist barrel

[Notalentbum]

I primarily load for precision shooting so the majority of my rifles have either 7 or 8” twist barrels using 75g Hornady HPBT projectiles. I have a few thousand 55g that I use for plinking ammo. I’ve always read that 7” twist is too fast for 55g accuracy. I’m curious if I’d be wasting my time trying to work up a load for sub moa accuracy.
I’ve shot a good bit of factory 55g stuff through a couple rifles that easily manage sub moa on 75g but are lucky to get below 5 moa on the factory 55g stuff. I have lots of Ramshot Tac that I’d be using and would eventually want to load it from my Dillon 650 but would do load development on my single stage, if it’s worth the effort.
What do you think?

Thanks, Matt

 

[55fairlane]

Ahh I call BS .......load em and choot'em.......my 100-yard practice ammo is 55 grain 223 I load....they group well outa my RRA national match with a 1 in 7 twist

 

[Notalentbum]

Ahh I call BS .......load em and choot'em.......my 100-yard practice ammo is 55 grain 223 I load....they group well outa my RRA national match with a 1 in 7 twist

I honestly didn’t know, just what I have read. No idea how much the faster twist really affected the accuracy. I guess I’ll load up 50 or so ladder loads tomorrow.

Thank you!

 

[55fairlane]

I honestly didn’t know, just what I have read. No idea how much the faster twist really affected the accuracy. I guess I’ll load up 50 or so ladder loads tomorrow.

Thank you!

You don't need 50 for ladder loads, load 10 round on .2 grain increments DOWN from max. EXAMPLE 30 , 29.8 , 29.6 , 29.4 you get the picture. Now shoot thru your clock, you will see 3 shot on the low end with almost identical velocity & 3 shots on the high end with almost identical velocity. The lowest charge on the high end is your load. This works, I promise!

 

[Notalentbum]

You don't need 50 for ladder loads, load 10 round on .2 grain increments DOWN from max. EXAMPLE 30 , 29.8 , 29.6 , 29.4 you get the picture. Now shoot thru your clock, you will see 3 shot on the low end with almost identical velocity & 3 shots on the high end with almost identical velocity. The lowest charge on the high end is your load. This works, I promise!

Definitely an approach I’ve not heard of!
I’ve always just shot for best group of the ten loads and pick the one with highest powder weight. Then start playing with OAL and fine tuning the powder weight.

 

[Basher]

I’ve always read that 7” twist is too fast for 55g accuracy.

Sub-MOA is probably a pipe dream. A bulk-packed FMJ of any weight is not likely to approach the accuracy of a quality BTHP. That being said, if you just want to ring steel then have at it. My 1:7 ARs shoot M193 to 300y and have no problems hitting a 2/3 IPSC all day at that distance.

 

[ROLEXrifleman]

If the projectiles are plinking grade then you will still get plinking grade accuracy from a 1:7/1:8 barrel.

With that said, I use Berger 52gr and 55gr target bullets and in both a 1:7 and 1:8 barrels am consistently get .5-.75" groups with stick powder.

 

[DadSmith]

I primarily load for precision shooting so the majority of my rifles have either 7 or 8” twist barrels using 75g Hornady HPBT projectiles. I have a few thousand 55g that I use for plinking ammo. I’ve always read that 7” twist is too fast for 55g accuracy. I’m curious if I’d be wasting my time trying to work up a load for sub moa accuracy.
I’ve shot a good bit of factory 55g stuff through a couple rifles that easily manage sub moa on 75g but are lucky to get below 5 moa on the factory 55g stuff. I have lots of Ramshot Tac that I’d be using and would eventually want to load it from my Dillon 650 but would do load development on my single stage, if it’s worth the effort.
What do you think?

Thanks, Matt

The only 55gr FMJBT that my 1-8 twist likes is Fiocchi green 50rd box ammunition.



It shoots same point of impact as my 75gr Hornady match hand loads.
XM193 all my rifles dislike no matter who makes it.
Since you're going to reload try to find a load it likes powder, bullet combination. Maybe you'll get lucky and it shoots poi like your 75gr.

 

[55fairlane]

Definitely an approach I’ve not heard of!
I’ve always just shot for best group of the ten loads and pick the one with highest powder weight. Then start playing with OAL and fine tuning the powder weight.

A) the method I described works....load development on Wednesday night, load ammo Thursday night, double check rifle zero Friday night, shoot long rang match Saturday morning.
B) with a 55 grainer (in 223 or 22-250) load the cartridge magazine leanth and "send em" ......
C) something to consider.....I picked up several CMP Match medals (in modern military) using 55GN ammo.....and 55 gn ammo is my 100 yard offhand/practice ammo.......if you do your part, the ammo&rifle will do there part.......now go out, find your sling, drop in to prone and "go clean" that Xring is teasing you

 

[Leo]

COLT H-Bar models are 7 twist and are pretty accurate with any weight. I have shot some really good Master level scores in High power with the little 52 grain Sierra bullets out of a 7.7 twist Krieger barrel on a reduced course including a 200-10X on the prone slow fire target. The X ring on that target is the size of a dime.

I did witness a problem at Camp Perry with the Berger VLD in fast twist. Those are really good target bullets. The man was known to load very high pressure ammo and was shooting a 7 twist. He was a Msater level shooter, so we know he was not missing the target. He fired his 10 round string, only 7 or eight made it to the target. He was allowed a refire and the range officer and several shooters watched. The competitor had perfect form and the rifle functioned flawlessly. We all noticed that a couple shots had a big puff of debris from the ground about 30 yards out. The target was again missing hits. The centrifugal force was spinning the jacket off. I am told that a .220 swift would do that if loaded to the max with some bullets. Unless you are loading VLD's in a load so hot the primers look melted, I don't think there is anything to worry about.

 

[Creedmoor]

COLT H-Bar models are 7 twist and are pretty accurate with any weight. I have shot some really good Master level scores in High power with the little 52 grain Sierra bullets out of a 7.7 twist Krieger barrel on a reduced course including a 200-10X on the prone slow fire target.

I did witness a problem at Camp Perry with the Berger VLD in fast twist. Those are really good target bullets. The man was known to load very high pressure ammo and was shooting a 7 twist. He was a Msater level shooter, so we know he was not missing the target. He fired his 10 round string, only 7 or eight made it to the target. He was allowed a refire and the range officer and several shooters watched. The competitor had perfect form and the rifle functioned flawlessly. We all noticed that a couple shots had a big puff of debris from the ground about 30 yards out. The target was again missing hits. The centrifugal force was spinning the jacket off. I am told that a .220 swift would do that if loaded to the max with some bullets. Unless you are loading VLD's in a load so hot the primers look melted, I don't think there is anything to worry about.

Ive done it over rotating Sierra 52 grainers and Hornadys 55 SX bullets.
Like you posted, a quick gray puff about 30 yds out.

 

[DadSmith]

Another thing it probably depends on what a person thinks is accurate.
If it isn't 1.25 MOA or less than it isn't accurate IMO.