[johnce59]

I have a Cooper in a .17 mach 4 and need some reloading data for using the Kindler 25 grain golds. Tried 19.3 grains of Benchmark yesterday with fairly good results but fairly certain it can do better. Your help is greatly appreciated.

 

[Norm in Pa]

H322

I've shot Benchmark and it does pretty good but my rifle likes H322 better. The load I'm using is 17.5 grains under the 25 Hornady hollow point. Be sure to start about 10% below that and work up. Things happen in that small case in a hurry!

 

[Kyle]

I shoot Benchmark but I can only get up to 18.8 gr safely with 25s, 19.2 with 20s in my gun.

 

[vmthtr in green bay]

I have an Excell file with a bunch of data on it for the 17 Mach IV. Send me an email and I will forward it to you. Was compiled by Tom Moore on Saubier.com

Mike

 

[Gapmaster]

17 Mach 4 loads

Here's a few.


25 grain Starke with 17.8 grains N-133 3850 FPS

25 gr Berger, 17.8 gr. N-133

18.4 Grs of H335 and 25gr Bergers

18.6 gr. H322 20Gr. V-max or Berger


Gapmaster

 

[Ackman]

For years H335 was pretty much the powder for a MachIV and it shot well in my gun. But that stuff can vary quite a bit from lot to lot. The accuracy load with either Hornady or Rem. HP's was very conservative and even so, I lost many primer pockets and came home at least once with a stuck bolt....pressures can skyrocket if ammunition gets hot from sitting in the sun. I'd stay away from H335. My current rifle likes VV135 and AA2230 with 25gr bullets......

19.2/135/25Hammett=3879 w/Rem.7-1/2. 3919 w/BR4.....same accuracy with both primers

With VV133, accuracy not as good, but best at 18.9gr/4054 and 19.3gr/4145 with Rem.7-1/2 primer.

Best with AA2230 was 19.8gr=3986....either 25Hammett or 25Calhoon, BR4 primer.

Be aware that AA2230 can also vary quite a bit from lot to lot.

Early PacNor 23" barrel 5 grooves, .195"nk, 0 freebore.

Try different bullets, because you never know. One load sequence with 2230 powder testing 25Hammett vs 25Berger....Bergers grouped 3/4" to almost 2", but the same load with Hammetts and groups shrank to where a couple of them had the holes all touching.

 

[Paul Workman]

Good stuff here. Just to add..

FWIW, I'll chime in and say my 'M4s favorite load to date is approx 20 gn of H335 under a 20 HP. Mine is a T/C Bullberry which cuts 5-shot groups at 100 yards ya can cover with a dime. The chrono says 3900 fps...crows, grackles, and starlings don't say a thing, but look like they ate a golf ball sized chunk of C-5 explosive!

But, what I was going to add is, I would highly recommend weighing loads for this caliber, unless you are using a ball powder like H335 (that meters extremely well and consistantly). A couple 1/10ths variation common with many other powders and thrower combinations amounts to a +/- 10% variation in load which is EXTREME in a case this size. Just beware.

You're gonna love the little 17 Mach IV!

P.

 

[vmthtr in green bay]

I am using VV133 and a 20g Vmax for 4110 fps and great groups. Prairie dogs hate it. Low recoil and good damage makes this my favorite bipod gun.

Mike