22 Creedmoor Development

[Mojo]

Starting this thread for my 22 CM load development. Just made some dummy rounds seated to the lands of chamber with .100” freebore. Barrel is 7.5 twist, 24”.

Planning to start with RL16 and RL26 for 69AH and 74HHT

From left to right - 69 AH, 68 HHT, 74 HHT, 88 ELDM.

 

[BFD]

This is an incredibly appealing visual picture here! I am excited for you! That 22CM is going to scream those things. No worries about losing jackets on the Hammers! Are you going to give the Hammers some jump?

Hammers - check
Peterson - check
Bleacher blocks - check
FX120i - whoah

Do give the details of forward progress!

 

[Mojo]

Will do! Yea I’m a little worried about the ELDMs. I probably won’t load those. Just wanted to see where they sat.

I typically aim for .020” jump and make adjustment based on bands.

Open to suggestions on all fronts.

 

[BFD]

Did some light reading on the 22CM. What I read, keeping the projectiles 3200 and under seem to prevent in flight jacket separation and extend barrel life to 1200rnds. Of course, you can turn up the velocity on the Hammers. LOL
I start Hammers .020 and usually end up .050ish. Sounds like a plan.
Popular powders are H4350, RL23, RL16, RL26. H4350 and RL23 seem most efficient.

 

[Mojo]

Finally got a chance to test some loads. I will probably end up with a load for 68HHT ~ 3700 fps and 74HHT ~ 3600 fps. There was room in the case to push the AH's faster, but I like the look of the HHT groups during the ladder test... impressive!


69AH, 37-45 gn RL16, 3037 - 3769 fps
68HHT, 37-44 gn RL16, 3188 - 3732 fps - red dots too hot
74HHT, 37-42 gn RL16, 3095 - 3506 fps
74HHT, 39 - 46.5 gn RL26, 3045 - 3623 fps




100 yds

 

[littlebighorn]

Hammers - check
Peterson - check
Bleacher blocks - check
FX120i - whoah

That's a Whoah for me too!
Very nice.

 

[gltaylor]

Either load will hunt!
That's the kind of ladder I love to see!
Who was it recently asking about "tuning" a load?
Perfect example of what to start with

 

[DanaR NY]

You gotta run the 33 or 35 at 5k, you got more case capacity than my 22 weatherby rocket

 

[littlebighorn]

I've only run the 60HH, 70HH, and 68 HHTs in my 22 CM, but mine's a 1:8 which limits my choices.
I'm still tuning mine, as well, but I'm super impressed with your ladder groups.
Keep it coming Mojo.

 

[unclecroc]

Awesome ladders and targets. That dog will hunt.

 

[Mojo]

Here are the raw numbers with notes on pressure signs.


22Creedmoor, 22CM
Barrel 24” Twist 1:7.5"
Brass Peterson
Primer Fed 210
No crimp

---

Bullet 69AH
Powder RL16
37 - 3037
38 - 3155
39 - 3259
40 - 3312
41 - 3388
42 - 3495
42.5 - 3533
43 - 3571
43.5 - 3614
44 - 3685 - very faint ej/ex mark
44.5 - 3714 - faint ej/ex mark
45 - 3769 - faint ej/ex mark

---

Bullet 68HHT
Powder RL16
37 - 3188
38 - 3217
39 - 3311
40 - 3412
41 - 3526
42 - 3600
42.5 - 3624
43 - 3638
43.5 - 3700 - very faint ej/ex mark
44 - 3732 - ej/ex mark
44.5 - 3810 - ej/ex mark, large primer crater, primer crater protruding - OVERPRESSURE
45 - Hell no

---

Bullet 74HHT
Powder RL26
39 - 3045
40 - 3108
41 - 3200
42 - 3255
43 - 3344
44 - 3458
44.5 - 3485
45 - 3533
45.5 - 3571
46 - 3609
46.5 - 3623 - very faint ej/ex mark

 

[gltaylor]

Thank you sir!
Please put final results and OAL in the share your Hammer loads post when done. I've got these (above) on the worksheet.
GL