Groups

[edge]

Tim, I machine my own sabots on a CNC lathe from PVC Type II.

The bullets are 0.308 150 grain AccuBonds While they aren't 300 grain SMKs, the BC is listed at 0.425 which means that they are still supersonic at 1,000 yards.

 

[davewilson]

don't know anything about a bad bull ML but by the looks of your groups i'd say you might have bedding problems, or as someone else said, a scope or mounting issues.

can i ask why you use 2 different powders? doesn't make sense to me but i'd like to hear.

if you only want to shoot out to 300 that can be accomplished with a regular muzzleloader.i've shot some nice bucks at just a shade under 250 with 300 being my limit.

as far as i know i still have the world record typ whitetail with a ML,but i only shot that at 100 yds.

 

[Fotis]

Double group = optics or bedding.

 

[edge]

[ QUOTE ]
SNIP

can i ask why you use 2 different powders? doesn't make sense to me but i'd like to hear.

SNIP

[/ QUOTE ]

A problem with shooting smokeless powder is that it needs pressure. Since we shoot sabots we don't have the luxury of the pressure rise as the bullet is swagged into the bore.

The duplex powder gives the pressure rise needed. I have tried shooting straight H4198 and the muzzle flash is horrendous! Using a duplex load allows the use of relatively slow powders.

edge.

 

[Coyboy]

edge, very interesting, never realized guys were doing such extreme things with a front loader. Please do us all a favor and start a new post in the equipment review section.

Please post pic's of rifle, and your process for cnc of those sabots, include your experience with load development. I'm sure most here are very interested to learn more.

You may have a new buisness selling sabots!

Very cutting edge stuff, keep us posted.

 

[davewilson]

why do you want to use relatively slow burning powders? i would think with a 50 cal bore one could use a fairly fast powder.would also help to raise the pressure a little quicker if that's what you want. is it because of the noise?

 

[J E Custom]

Edge

First let me say WOW 3100ft/sec.

Now let me tell you my experence with duplex loads TERRIBLE,
BAD, LOUSY etc.

First I would try one type of powder.

As far as sabots I found that much over 2000 ft/sec
they would skip the rifling and lose accuracy.

Remember when remington sold the excelerator .They
were very fast but nothing I owned would shoot well
with them.

Maby some of the other guys have had better luck than
me and can help you.

J E CUSTOM

PS Be very carefull with duplex loads because if they are
not compressed they can be extremly dangerous.

 

[edge]

My rifle is a .458

One major problem with a muzzleloader is that there is an open flash hole when the primer is not in place. This limits powders to the bulkier ones.

Another problem with sabots is that you are looking for a high average pressure but not necessarily a high peak pressure. 70 grains of powder would indicate either a powder in the range of 4227 or 4198.
4227 gives poor accuracy in my rifle at these loadings and 4198 does not burn completely.

Others have found that by using a duplex powder you can tailor your powder speed to match what the rifle likes. I tended to stick with the faster powders for a long time, but could never get much under 1 moa with my groups.

In my 505 Gibbs barreled muzzleloader straight N110 does give good results with a slightly heavier bullet/sabot combo.

J E Custom

In a muzzleloader every load is compressed.

If you look at the picture of my sabots, you will see that they are fully rifled on a lathe. I have never had one strip due to velocity. I did have a problem with the sabot petals not breaking off cleanly which I believe made the sabot tip. This caused fliers from the group by pushing the bullet off course. Finding the correct spot for the petal groove solved that problem.

edge.

 

[J E Custom]

Edge

As one of the other guys said you know a hell of a lot
more than I do about muzzle loaders but what I ment by
compressed loads was when I tried duplex loading
I was told to compress each powder as it was placed in
the barrel.this helped to minimize mixing and finger
nailing (allowing slower powder to get behind the faster
priming powder charge. As this would cause different
burn rates.

It looks like you have gone to a lot of trouble with the
sabots so I am not sure what you can do to improve over what you all ready have.

I had trouble geting under 2moa @ 100 yrds so I switched
to heavy lead bullets and barns x ( 620 gr sp fb 50cal &
500gr triple shocks for my 45cal) I know that they rainbow
badly but will shoot 1 to 1.25 moa at 600 yrds with iron
sites and retain lots of energy.

Also I use the 450gr & 500gr triple shock in a 45/110 sharps
loaded with 777 and it shoots under 1moa (.812 best so far)

I am interested in what you come up with so please post the results.

good luck
J E CUSTOM