17h loads

Cgeorge1104

New member
Trying to develop a load for my CZ527 in 17hornet and keep having issues. I usually do a ladder test and find what charge it likes the best. I get it to group tight with a load and when I recreate the exact load and try to group again it opens way up. I’m talking sub moa groups then I load more up the same and it then groups like 1.5-3”. It will put 5 shot groups in a nickel then open up.

I’ve been doing H4198 and 25gr Hornady HP but I’ve also got a little bit of 17gr vmax and 29gr woodchuck dens. About 100 of them but 500+ of the 25s since the 17-223 likes them I was hoping the 17hornet would also.

What loads have y’all had luck with and the hornet. I can’t seem to find load data for the 17gr I was gonna try them next and if that doesn’t work out maybe mess with different powders if I can track some down.
 
I have two CZ 527 Varmint model 17 Hornets and they both like 12.2gr 1680 with 20gr Vmax lit off with Rem 7 1/2 primers. I've tried from 12-12.4gr of 1680 but mine shoot their best with 12-12.2

The brass and the chambers in these CZ 17 Hornets don't match up very well until they've been fire formed to the guns chamber. The brass is a tick undersize and the chambers on these CZ 527's is long. After they've been fired you'll often notice, just above the rim, a stretched section. Many, mistakenly refer to it as bulged but it's actually just the opposite and if you measure it with a caliper that section above the rim will be smaller in diameter, not larger. They cost a little more but I use the Redding 3 die set that has a bushing neck size only die and only neck size my 17 Hornet brass. Once it's grown to the point it won't chamber, only then do I run it through the body die and bump the shoulder back but it generally takes a few firings before I need to. If you're using a standard FL die with your 17 Hornet you'll want to be mindful of how you set up you FL die and not over size your brass because if you regularly push it back to factory length you'll start getting case separation in no time.

Sometimes, these 17 Hornets can be finicky little buggers and make you start chasing your tail. Maybe give the 20gr Vmax a try with 1680 or BLK CFE. I've had good luck with 1680 and the 20's but I know plenty of others that have found success using BLK CFE.
 
Duplicating group problems can be caused by(excluding optics,stock,bedding, screw problems and shooter errors)
1.wind not using flags will cause many issues testing loads on multiple days.
2.cleaning the firearm between range/testing days
3. Resetting dies, a lot of us use a single press. Brass sizing, bullet seating changes can alter grouping.
4.powder measuring and scale accuracy can be affected by humidity changes.
5. Brass condition(carbon residue) contamination(moisture,lube) and case hardening. Can cause velocity,pressure and inconsistent ignition.
6. Small calibers/case are more sensitive to small variations.
7. Big problem load is not in a good node that allows for small inconsistencies(charge weight,seating depth).
8.twist rate/bullet combination is border line for stability(increases wind problems down range)
 
Originally Posted By: DecoyedMake sure your trimming your cases every time. Had it happen on a 22 hornet

you had what happen?

i very seldom have a need to trim cases. my cases develop split necks way before they are in need of trimming. that goes for every rifle i own.

i don't spit polish my brass either. it's lucky if it gets wiped with a old sock with holes in it.

i know. pure heathen. lol
 
Originally Posted By: B23I have two CZ 527 Varmint model 17 Hornets and they both like 12.2gr 1680 with 20gr Vmax lit off with Rem 7 1/2 primers. I've tried from 12-12.4gr of 1680 but mine shoot their best with 12-12.2

The brass and the chambers in these CZ 17 Hornets don't match up very well until they've been fire formed to the guns chamber. The brass is a tick undersize and the chambers on these CZ 527's is long. After they've been fired you'll often notice, just above the rim, a stretched section. Many, mistakenly refer to it as bulged but it's actually just the opposite and if you measure it with a caliper that section above the rim will be smaller in diameter, not larger. They cost a little more but I use the Redding 3 die set that has a bushing neck size only die and only neck size my 17 Hornet brass. Once it's grown to the point it won't chamber, only then do I run it through the body die and bump the shoulder back but it generally takes a few firings before I need to. If you're using a standard FL die with your 17 Hornet you'll want to be mindful of how you set up you FL die and not over size your brass because if you regularly push it back to factory length you'll start getting case separation in no time.

Sometimes, these 17 Hornets can be finicky little buggers and make you start chasing your tail. Maybe give the 20gr Vmax a try with 1680 or BLK CFE. I've had good luck with 1680 and the 20's but I know plenty of others that have found success using BLK CFE.


I run Hornady FL dies. I found some BLK on midway I might order some to try it but wanna see if a co worker needs powder also to ease the blow of the hazmat charge to ship powder.

I got 2 boxes of Hornady brass off gun broker only place I could find it granted it ranged from $45-80 for a box of 50 I got 2 at 45 I only had 2 boxes of factory ammo I’ve been using the once fired to do my reloads.
 
I also have the CZ527 varmint. For the 20 grain Vmax I found that it likes CFE BLK at 12.4 grains at Hornady factory COL. For a 25 grain Berger varmint bullet I settled on 12.2 grains of H335 at the Berger manual COL. I struggled to find a powder the rifle liked at first. The usual AA1680 and AA2200 were out of stock forever. Both of the loads I listed are 1/2 moa or less if I'm shooting straight. Using Remington 7 1/2 primers. I've never used the 25 grain Hornady yet, just thrilled to find two accurate loads. Saubier.com is your friend on small caliber stuff. Good luck.
 
Last edited:
Back
Top