1:10 twist .308 cast @ 2605fps at 500 yards sub 2 MOA five shot group.

[waco]

Perfect..
Will be ordering one of these molds next month, Merry Christmas to me, lol..
And thanks for your reply..

You are welcome.

[GregLaROCHE]

It's all theory, but if the limiting factor with the velocity of cast bullets is the alloys ability to hold rifling, I would think a bullet that is all bearing surface would hold the best. Maybe not. I now want to try some higher velocity bullets in my 308 Winchester 1:10" twist. I'll see how far the Lee 309-170-F will hold up. I was thinking a 200 grain bullet with just enough lube, all bearing surface, and a very short nose should be the best you will get. I've got one drawn up. I don't understand why the Loverin designs have the tiny drive bands, especially since so many recommend only filling half with lube. I would think 3 small lube grooves, with hefty driving bands would be a better way.

I can’t say from experience, because I haven’t tried it, but I have heard a lot about the difference between of boolits being hard and tough. I have had hard boolits come apart on me, so have tried to find out as much as it can on the subject. It’s been said that adding a little copper to the alloy makes it tougher and more able to stand up to the rifling with high speed boolits.

[Larry Gibson]

Interesting. I was looking at NOE's site and they show "how to seat" this boolit and it has the GC in past the neck and a COL of 2.629". I have a different mold that is the 311-174-FN-AQ5 and I size to .311. I've only made dummy boolits so far to test the fit/function in my rifle and I found that if I seat it at a COL of 2.7" then about 0.07" of the boolit is past the neck and the boolit is about 0.005-0.01" from touching the lands - too close to measure with my calipers. But this is how NOE shows how to seat the 30 CXB...

These things are interesting... A little bit here and there makes things work or NOT work. I cannot wait to load and shoot my boolits.

Thanks again for the inspiration!

Attachment 230401
http://noebulletmolds.com/NV/product...roducts_id=915

Note that the top of the GC is still in/at the base of the case neck. That is the proper max seating depth. Injury to the bullet from gas cutting can occur causing leading and inaccuracy. Non-crimp on GCs could also be scraped off by the case neck base causing further problems. These problems don't always occur as a lot depends on the alloy used, powder used and the intensity of the load. In the NRA Cast Bullet Supplement there is an example of what can happen to the bullet if seated too deep into the case;

Attachment 230411

The bullet on the left had the GC seated still in the neck. The bullet on the right was seated with the GC below the neck.

[44Blam]

Note that the top of the GC is still in/at the base of the case neck. That is the proper max seating depth. Injury to the bullet from gas cutting can occur causing leading and inaccuracy. Non-crimp on GCs could also be scraped off by the case neck base causing further problems. These problems don't always occur as a lot depends on the alloy used, powder used and the intensity of the load. In the NRA Cast Bullet Supplement there is an example of what can happen to the bullet if seated too deep into the case;

Attachment 230411

The bullet on the left had the GC seated still in the neck. The bullet on the right was seated with the GC below the neck.

Looks like time to do some measuring and calculations as to were things actually are before I start shooting. I have some time to think about it anyway.

[megasupermagnum]

Something about that just seems fishy. If the bullet is a proper size, how would it be gas cut just because the gas check is blow the neck? Pressure would be very low at that point. i'm not aware of anyone using non-crimp gas checks anymore. I've been doing some research, and mtngun of Mountain Molds regularly shoots with gas check below the neck. He is shooting every bit as good as I'm seeing here, maybe better. Not to call anyone out, it just seems that people are finding success in completely different ways, which is so often the case in cast bullets.

[GregLaROCHE]

It seems to me, that if the GC is below the neck, the hot gases are going to be past the CC, that is supposed to seal them off, before the boolit begins to move. The GC may not even stay on.

[megasupermagnum]

It seems to me, that if the GC is below the neck, the hot gases are going to be past the CC, that is supposed to seal them off, before the boolit begins to move. The GC may not even stay on.

And yet, there is the rest of the bullet in the neck, no different than a plain base. I'm willing to bet pressure and velocity is extremely low while the bullet is still in the neck. Why wouldn't a crimped on gas check stay on?

[waco]

Almost any 300 blk Load is seated way below the neck.
Same on a 300 Savage.

[Larry Gibson]

It seems to me, that if the GC is below the neck, the hot gases are going to be past the CC, that is supposed to seal them off, before the boolit begins to move. The GC may not even stay on.

That is correct. The hot gases can erode the bullet in some instances such as the NRA CB Supplement photo demonstrate. As stated earlier how much occurs and whether it has any discernible effect on accuracy depends on many variables. Fact of the matter is I know of no CB bench rest shooters who seat GCs below the neck. If your rifle/load is 2-4 moa capable or you're shooting at close range then the adverse affect probably isn't discernible either, unless leading is a problem.

Crimp on GCs, if seated and crimped correctly, probably won't come off. It's the older non-crimp on slip fit GCs or the now home made thin non-crimp on GCs that pose the problem of coming off inside the case, particularly those that are a loose fit to begin with.

[Shopdog]

Nice job Waco! I regularly shoot high velocity out of tight twist barrels. My '06 CDL is a tackdriver @2800. Would love to shoot some steel at 500 but,don't have a convenient range.

[GregLaROCHE]

When a crimped on GC is referred to, it’s the type we normally buy or make and it is seated and crimped in place while the boolit is being sized. Right? I haven’t missed something where a GC is crimped on like factory crimp die crimps the case to the boolit?

[charlie b]

I believe Larry is referring specifically to the Hornady style gas checks rather than the 'straight side' gas checks that people can make at home. The difference is the 'edge' that Hornady puts on the gas check. When seated the GC is 'crimped' and makes a kind of groove in the heel of the bullet. As such it will not slide off the bullet without a bit of force.

The std GC's have straight sides so are dependent on sliding friction to stay on the bullet. They can be pulled off the bullet more easily. I would not seat one of those below the neck of any cartridge.

I've also used the XCB bullet in my .308, but, I powder coat and the Savage has a short throat. When seated and partially jammed into the rifling the gas check is well below the neck of the case. I have had some good groups with it when fired in the 1900fps range and even some great groups when fired at the 1100fps range. But, when the velocity goes up accuracy drops (also a 1:10 twist). I am still working with it to find out if I can push it any harder. I have been trying to recover some of the bullets so I could see what the bases and drive bands look like but have not had any luck so far.

[44Blam]

I love the left side camera.

[DonHowe]

I cannot shoot like that with jacketed. At 500 yards, the wind will get to me, even if the gun and load are capable. A 10 MPH wind will give over 2 ft of windage. Great shooting waco.

EVERYONE has to deal with the wind regardless of bullet material, velocity, etc. At high velocity the wind effect is less but still there,
even when in your face or at your back. In tricky wind put a 1400 fps boolit on target at 100/200 yes with wind in your face then fire one with wind at your back and watch your POI vertically.
If you set a flag every 100 yes to 500 yes, chances are they won't all read the same and air currents can vary between flags.
It' a fact of life.

[Cosmic_Charlie]

Very nice work there! I like the cheap seats though, sub moa @ 50 yds. with gc cast. Useful distance for pest control and fun. When I want to go long I shoot .223 ball ammo out of an AR.