300WM Faster Than Expected

[Warrenoliver]

I know all rifles are different but I have a Bergara 300wm that loves this recipe so I used it as a starting point.

Would be interesting to try those same loads in your Bergara to see what kind of speed you get

 

[PApa Black]

Berger says 1:11 or faster and I'm running a 1:10 twist. This gun may very well not like the H1000 or Bergers but my SD and ES are pretty good at 75.2 and 75.5. Will see if seating depth can close up that group.

Berger bullets are very tricky to tune. That's all I shoot. In my 308s 0.160" off the lans was the spot. And they don't go to sleep until pass ~300yds. The group at 100yds (1.0") is the same at 500 yds: 1.0". So that's about a 0.2 to 0.3 MOA! Enjoy the journey That's for the 168gr VLD.

 

[FEENIX]

I have a 300 WM in a Husqvarna 9000 with a 1-12 twist.
That is what the Nosler #1 book says.
I have only Crono-ed it one time years ago ,but 75 gr of RL22 produced 3110fps.(180 gr Nosler Partition)
At the time that seemed faster than I expected!

Out of respect to the OP (@jstanton), you might want to consider a separate thread for your specific query and yield results dedicated to your issue/concern and not get mixed up or buried on this thread. Good luck!

 

[Flatbow]

Berger load data doesn't use adg brass--- iirc adg recommends dropping a full grain of powder when using their brass

Here is a quote from their website :
" With the additional material, our brass is heavier than most other manufacturers brass and therefore will require lower charge weights to achieve the same pressures and velocities due to the reduced volume inside the brass"

I have wondered why the berger book always seemed to be a bit on the conservative side with their load data.
This may be the reason...?

 

[MTbackwoods]

So, for those who commented on my Bone Head Mistake thread, I did not use the blended H1000/H4831SC for what I'm about to say!

Doing load development on a factory Christensen Ridgeline, after following factory break in procedure using factory Hornady 180gr Superformance ammo. I loaded up some 210gr Bergers in new ADG brass, Federal 215 LRM primers, .040" off lands, .002" neck tension, and a new 1lb can of H1000. Berger book says max load 75.5 at 2804fps, I know it's not always gonna match but it's a good average expectation.

Shooting conditions: Temperature 60⁰F, Humidity 25%, Elevation ~500', Wind 8mph WNW.

5 Shot groups, measure speed with Garmin Xerox C1

Charge Avg FPS SD ES
74.7 2894.5 8.0 22.0
74.9 2904.8 6.9 20.4
75.2 2925.1 5.3 14.8
75.5 2928.1 4.6 14.3
75.8 2938.5 17.5 49.4

All shots grouped horrible but there seems to be a decent node at 75.2 and 75.5 but those groups were 1.5"-2" though.

First I'm curious as to why my results are so much faster than book? Never had any signs of pressure but maybe a slightly sticky bolt on the 75.8 group. Was hard to tell as the action on this Christensen is a little tight naturally after a fired round. Second can I wrangle this load in by adjusting seating depth?

I know all rifles are different but I have a Bergara 300wm that loves this recipe so I used it as a starting point. With that rifle, doing seating depth tests, the worst groups were around .80"-1.0" and when I finally settled on .040" off the lands I could get .50"-.60" groups as long as I did my part with 75.8gr of H1000.

Not saying your issue reflects mine, but I'll tell you about my one and only experience with a Christensen. I bought an ELR about a year ago and did a work up with N570 and 225 ELDM. At 79.5 I hit 3,076 FPS. Should not be possible. I tested other bullets and always achieved crazy speed but the best group I ever got was about an inch. Don't know what caused it, didn't stick around to find out. Never again will I buy a Christensen

 

[PApa Black]

I have wondered why the berger book always seemed to be a bit on the conservative side with their load data.
This may be the reason...?

I asked Berger that same question: the answer is lawyers and liability.

 

[FEENIX]

I asked Berger that same question: the answer is lawyers and liability.

You could ask any bullet makers with their reloading manuals and probably get the same response.

 

[K.E.C. Darkside]

So, for those who commented on my Bone Head Mistake thread, I did not use the blended H1000/H4831SC for what I'm about to say!

Doing load development on a factory Christensen Ridgeline, after following factory break in procedure using factory Hornady 180gr Superformance ammo. I loaded up some 210gr Bergers in new ADG brass, Federal 215 LRM primers, .040" off lands, .002" neck tension, and a new 1lb can of H1000. Berger book says max load 75.5 at 2804fps, I know it's not always gonna match but it's a good average expectation.

Shooting conditions: Temperature 60⁰F, Humidity 25%, Elevation ~500', Wind 8mph WNW.

5 Shot groups, measure speed with Garmin Xerox C1

Charge Avg FPS SD ES
74.7 2894.5 8.0 22.0
74.9 2904.8 6.9 20.4
75.2 2925.1 5.3 14.8
75.5 2928.1 4.6 14.3
75.8 2938.5 17.5 49.4

All shots grouped horrible but there seems to be a decent node at 75.2 and 75.5 but those groups were 1.5"-2" though.

First I'm curious as to why my results are so much faster than book? Never had any signs of pressure but maybe a slightly sticky bolt on the 75.8 group. Was hard to tell as the action on this Christensen is a little tight naturally after a fired round. Second can I wrangle this load in by adjusting seating depth?

I know all rifles are different but I have a Bergara 300wm that loves this recipe so I used it as a starting point. With that rifle, doing seating depth tests, the worst groups were around .80"-1.0" and when I finally settled on .040" off the lands I could get .50"-.60" groups as long as I did my part with 75.8gr of H1000.

Howdy, you are right there with what I have with the same rifle.
With only around 80 shots on my barrel, so I believe it will get a little faster.
I settled on H- 1000 76.6gr
Peterson long brass 2nd fired
CCI250, 3.590. mag.length 3.600, 45thou.
Off lands. Settled on 2920fps
215 Hybrid . 1/2 moa out to 300yds.
Hope this helps.

 

[Argon Glen]

Sometimes ya luck into a fast barrel.