My try at HV cast

[Will]

First let me say thanks to all of those who have put up with a lot of my questions along the way, as I know they probably become annoying at times.

Today was my first day out to try and shoot cast bullets at high velocity. I was honestly surprised by the results and left with quite a few questions. My goal was to get a sub 1" groups at around around 2300-2400 fps but as you will see in my chronograph data I started a little too high.

All load were shot in my Howa multi cam 1500 with 22" 1-10" twist barrel. Optic was a Vortex Viper HSLR 4-16x40 30mm tube mounted up with warn rings and base. Shot were fired at 100yds at 1" birch wood casey stick on dots. All velocity reading came from my magneto speed V3 chronograph. I will post the data here and add pics with my cell in the next post. All ammo was loaded in WCC military brass, with a standard federal large rifle primer, and the mihec 308 hunting bullet cast with 50/50 COWW/SOWW and water dropped from the mold. I used 6-6-6-1 lube when running the bullets through a 309 sizer and installing a hornady gas check.

I shot 5 loads on Winchester 760 just to get an idea of where it put me in velocity. I only shot 1 round with each charge
43gr 2243fps
44gr 2332fps
45gr 2429fps
46gr 2463fps
47gr 2476

I loaded 5 shot groups with the following charge weights using IMR 4350
45.5gr AV vel 2452 fps SD15.7
45.8gr AV vel 2468 fps SD 11.3
46.1gr AV vel 2492 fps SD 13.4
46.4gr AV vel 2494 fps SD 19.0
46.7gr AV vel 2508 fps SD 14.2
47.0gr AV vel 2504 fps SD 22.5 not sure why the velocity dropped here

Later if anyone wants I can list the velocity of each shot. I feel that is where the most info is really to be gained at this point. Most of those stand deviations were from one or two shots in the 5 shot string. I think I really need to get my neck tension under control to shrink those down.

 

[Will]

Here’s the 100yd group pics. Sorry for the pics not being in order.

 

[Will]

The 45.5gr charge I think put 2 in the hole that’s in the 1” dot. There was 2 feet of clean cardboard all the way around the target that had no bullet holes.

 

[popper]

46.1 looks like it hit a node. Good job, isn't really that hard.

 

[Will]

To be honest popper I was blown away by the groups. I think I still have a smile from ear to ear.

I’ve read so much mainly on the other forum about how hard it is and how it can’t be done. When I seen I had went way over my target velocity I was planning on not being able to keep shots on the 4’x4’ target backer.

 

[fiver]

that's all I can do right now.

looking at your groups and such you can clearly see them open and close with each little change in the powder steps.
if a guy just threw some stuff together and hit a bad node right off, of course he would think it impossible.

however.
your looking at 2500 fps with some good and bad groups and are already thinking,, man if I only... or if I just.
your so sucked in now it'll be like crack for a while.

 

[fiver]

so umm 46grs and a slight oal adjustment?

 

[Will]

Sounds like something to give a try fiver. All of these loads were loaded out pretty far. Bullets had some slight scuff marks by the rifling right above the crimp groove.


I am having trouble figuring out the wild flyer on the 46.4gr charge. The velocity on that shot was about 20fps faster but nothing crazy.

 

[fiver]

shape of the hole would give a clue.
it might have lost a check?

so umm,, you still want that package?

 

[Will]

Yeah I think I have plenty of room for improvement. And I have another 308 so I’ve got lots more testing to do.

This bullet from what I can tell does fit great. I’ll know tomorrow after I do the pound cast.

 

[waco]

Awesome first results Will! Keep it up!

 

[fiver]

you'll soon discover why we start talking about stupid esoteric minutia at times.
it's for that last/next quarter inch.
a little tin, thicker necks, tape, mold temp, oven quenching 20 bullets, a little filler.
tiny little test strips around that edge of good.

 

[Ian]

that's all I can do right now.

looking at your groups and such you can clearly see them open and close with each little change in the powder steps.
if a guy just threw some stuff together and hit a bad node right off, of course he would think it impossible.

however.
your looking at 2500 fps with some good and bad groups and are already thinking,, man if I only... or if I just.
your so sucked in now it'll be like crack for a while.

Yep, just like crack. Keep tinkering, you'll learn as much or more from the backwards steps as you do with the forward ones, then you'll begin to get a picture of what does what and why. It's all about stuff going on inside the rifle, and all stuff you can manipulate.

 

[Will]

I tried to find some bullets in the bank behind the target but it was too muddy. I’ll go back down with a shovel and try to find some. I’m really interested to see what one looks like.

 

[Ian]

I bet the grooves were filled clear to the ogive.

 

[fiver]

if they are like mine all I get back is the gas check and some of the shank.
that's a pretty sudden stop.

 

[Brad]

For a first go that is awesome.

 

[Will]

I was pleased with the results but I want more. I’m really hoping I can get to to stay consistently under 1” groups.
But I really am impressed with this rifle. There is nothing fancy at all about. The barrel is a very slim sporter profile and the rifle is really light overall.
I’m curious what one of those bullets would do to a deer at 2500fps

 

[Rick]

Very impressive Will, congratulations. Looking forward to your next report.

 

[fiver]

well I know a250gr 358 at about 2350 through the higher shoulders will tip one over... literally.
if you use too much meplat and hit meat you won't need to grind it later.
there is a balance...