Thread: 223 69gr TMK / 77gr TMK damage to projectiles while seating

Once I got to compacting/crushing the ADI 2208 powder near max load I find that the projectiles get ringed/damaged by the seater. I have tried the hornady with amax (secant ogive?) and its not as bad as the Lee die but its still noticable and I need to go hotter still. Looking at the chrono, accuracy and load data chart for both the above projectiles I am going to need a denser powder than 2208 to avoid this damage as I need to be at or around max velocity so what powder is suggested? BM2?

My lee does the same on vlds and barnes tsx. I took out the floating seating part, put it in the drill and rolled up a bit of 1200 grit and gave it a good internal honing. Don't get the rings near the top of the pill now. They felt like they grabbed a bit too which was a shit if you wanted to run lower neck tension.

I'd rather not f with the stems.

I solved the ringing on 308w, HBCs and Lee by getting the hornady seater with amax stem, same trick didnt work with these 223s though

ADI factory and most accurate was,

69gr factory load
smk 2684
2710
2701
2676
2701
13472
av2694.4

handload,

69gr tmk 24.8gr 2208
adi case 2612
2208 2598
2572
2591
10373
av2593.25
So I need to add 100fps to get near the node I think. Same with the 77gr TMK.

2206H?

2206H is indeed the other choice but it shows compressed at max load as well as the 2208 and BM2 gives me a bit more velocity uncompressed.

Bm2 worked well in mine wth 69gr although best velocity was with 2206h, it's a rare powder that actually seems to correlate with the aid data for velocity and pressure ...

@steven we are using 2206h in an adi case with 75 grain amax doing 2810fps. It's a compressed load but only just

@puku, hey thanks, but I am going to try BM2 first though as it isnt compressed at all. I just need to find someone selling 500g, so far its all 1kg. From my initial loads I think the accuracy node is right up at the load limit (as I increased the charge the SD and accuracy improved) for both 69gr and 77gr so not compressing seems the safest way to experiment near the limit Once I can see which is the most accurate I might try 75s unless 77s do better and then maybe 80s, but I'd be surprised in a 1 in 9 twist if 80s fly.

How do you find getting 75s? they dont seem to be as commonly available?

@steven to be honest the 75 gr was easier to get than what I thought. I bought a 600 box from gunworks.
What head stamp do your adi cases have?
Also @7mmsaum swears by 2208 with the bigger .224" projectiles. Maybe you need a hotter primer?

Originally Posted by steven

@puku, hey thanks, but I am going to try BM2 first though as it isnt compressed at all. I just need to find someone selling 500g, so far its all 1kg. From my initial loads I think the accuracy node is right up at the load limit (as I increased the charge the SD and accuracy improved) for both 69gr and 77gr so not compressing seems the safest way to experiment near the limit Once I can see which is the most accurate I might try 75s unless 77s do better and then maybe 80s, but I'd be surprised in a 1 in 9 twist if 80s fly.

How do you find getting 75s? they dont seem to be as commonly available?

I will swap a new bm2 container for a 2208 or 2209 if you like.
Pm if you interested.
Mac

Steven,
There is another trick to lift your powder capacity in the smaller cases, actually any chambering, -neck size only

Just replace the primer and neck size 3/4 of the neck length

The unsized portion of the neck will self align in your rifles chamber neck and improve accuracy

You will get two more grains of 2206H/2208 powder in a 223 case with a partial neck size only

Don't forget on the 6 mmbr website under the 223 page there is a list of 223 brass manufacturers showing their internal case capacity

Long throated rifles like Tikkas and Sakos allow you to use ammo with a longer overall length, with the projectile seated out, this increases powder capacity

So, if you have brass with the largest internal capacity, a projectile seated halfway down the neck in partially neck sized brass you can see 3400fps with 60g Nosler ballistic tips and 2206H, 100 fps slower with 2208.

Keep the 75g a-max under 3100fps, in a 1-8 twist they tear apart with a boom about 80yrds out, with the target untouched

@7mmsaum cant neck size on a semi-auto action (Ar15). I do need to check the chamber throat length but I suspect the throat is quite short, 2.265 is it anyway for the mag, though I am single loading on a platform now. I think my club has a hornady kit so I need to do that, hopefully next weekend. I am using HP match grade Sierra tmk bullets in a 1 in 9 and so far the 77gr seem the most accurate over the 69gr TMK but I have not tried 75s yet, Ive not seen them about. I posted speeds earlier but the best accuracy seems to be 2950 fps ish for the ADI 69gr factory, not chrono'd the xtac 77gr PMC smk factory load yet but they also shot very well around 3/4moa from a std 4140 stag barrel.