New 223 bullet selection

[Cory porter]

I just pictured up a custom barreled action from kampfeld customs. 1/8 twist 24in 223.

Also it's in a mcree chassis. I believe they only take aics mags(could be wrong)

So my question is this being my first mag fed bolt gun what bullets would you choose. The rifle will be used for steel and just a fun gun to shoot when I'm not using my bench guns. I currently have 73g bergers, 80.5 bergers, 80gamax and 69g smk laying around.

What would your starting point be. I also have about every type of powder for a 223 to try as well.

 

[mac86951]

H4895, varget, n140 fed 205M; or BR4. Depends on seating length for starting point.

 

[Texas10]

An 80 grain SMK is barely stable in my 22-250, 8 twist, 28" barrel going 3150 fps (I'm nearly at sea level) but my 223, 8 twist 26 in Criterion shoots the 75 grain BTHP Hornaday very well. So I think you can put the 80's away and concentrate on the 73 and 69, both should shoot well out of your 223 with 24 inch 8 twist. The 69 TMK is especially good for long distance.

Berger website has a good stability calculator. Check it out!

Remember, it's not so much the weight of the bullet, but the length to girth ratio and rotational speed that effects gyroscopic stability. Velocity X 720 divided by twist= rotation speed (RPM).

 

[JLT]

The 68 gr. Hornady BTHP is a nice little bullet and the price is right, too. I load 23.8 gr. of IMR 8208XBR behind that bullet with a CCI 450 SRM primer in LC brass and that load shoots very, very well in all of my .223/5.56s. If you're looking for speed, Alliant 2000MR can really push the medium-to-heavy bullets in the .223.

 

[TAJ45]

An 80 grain SMK is barely stable in my 22-250, 8 twist, 28" barrel going 3150 fps (I'm nearly at sea level) but my 223, 8 twist 26 in Criterion shoots the 75 grain BTHP Hornaday very well. So I think you can put the 80's away and concentrate on the 73 and 69, both should shoot well out of your 223 with 24 inch 8 twist. The 69 TMK is especially good for long distance.

Berger website has a good stability calculator. Check it out!

Remember, it's not so much the weight of the bullet, but the length to girth ratio and rotational speed that effects gyroscopic stability. Velocity X 720 divided by twist= rotation speed (RPM).

An 80 grain SMK is barely stable in my 22-250, 8 twist, 28" barrel going 3150 fps (I'm nearly at sea level) but my 223, 8 twist 26 in Criterion shoots the 75 grain BTHP Hornaday very well. So I think you can put the 80's away and concentrate on the 73 and 69, both should shoot well out of your 223 with 24 inch 8 twist. The 69 TMK is especially good for long distance.

Berger website has a good stability calculator. Check it out!

Remember, it's not so much the weight of the bullet, but the length to girth ratio and rotational speed that effects gyroscopic stability. Velocity X 720 divided by twist= rotation speed (RPM).

May I safely reason that the tw rate needs to be in feet or the velocity in inches? It's been a long time on the equations.

 

[mac86951]

May I safely reason that the tw rate needs to be in feet or the velocity in inches? It's been a long time on the equations.

Uhh, not sure what you mean; but I think you got it backwards. Twist is inches for 1 turn; velocity is in feet per second (fps)

 

[1lnbrdg]

For the Amax 80gr, your barrel had better be a 7-something twist. The 1/8 twists do not work.

 

[CharlieNC]

For fun on steel the Hornady 75gr Amax is a great bullet. I shoot it out of a 22" 8-twist barrel at about 3000fps. You won't believe the drops out to 900yd are exactly the same as my 6.5x47, but get progressively more out to the max I have shot 1100yd (close to sub-sonic). Of course the wind is more critical on the small pills. For serious accuracy I run the 80.5 in Ftr, but not necessary for steel. My friend tried the 80gr Amax and as mentioned the 8 twist did not stabilize it, but the bc is not worth it anyway. Great fun!

 

[swadiver]

for shorter range the 73 Bergers are super accurate. I also like the 80.5 Bergers in my 1 in 8 twist Bartlein bolt rifle for ranges out to 600 yds.. try IMR 8208XBR with the 73's, and H4895 with the 80.5's.

 

[TAJ45]

Uhh, not sure what you mean; but I think you got it backwards. Twist is inches for 1 turn; velocity is in feet per second (fps)

We're not quite on the same page. I was trying to convey that the units had to match, therefore change one to match the other. This could keep from dividing feet/second by inches of bbl twist. Converting of them to feet or inches.

 

[Texas10]

For example:

Velocity=3350
Twist 8 (as in one in 8 inches)
3350X720/8= 301,500 RPM

Another example where velocity=2900 fps in a 1/9 twist barrel

2900X720/9=232,000 RPM

 

[TAJ45]

Tha

For example:

Velocity=3350
Twist 8 (as in one in 8 inches)
3350X720/8= 301,500 RPM

Another example where velocity=2900 fps in a 1/9 twist barrel

2900X720/9=232,000 RPM

Thanks. It looks like it works without needing to put everything in like terms. I appreciate your answer.