Great at 50yds, ok at 100yds????

[abunaitoo]

I know this has been posted before, but I can't seem to find it.

308. Bullets 160gr GC. 700x. rifle primer. Cast at 313, sized to 311. WW water dropped. Carnuba red lube.
2A Enfield.
Shoots great at 50yds. About 1" to 1 1/2", sometimes three shots touching.
At 100yds 4" to 5" and all over the place.

What are some of the things I should be checking?????

[303Guy]

Mmmm .... If I may suggest from a position of test tube firing, rather than range tests ... [smilie=1:

Boolit base deformation (feathering at the rifling impressions). This can be determine by low velocity firing into some catch medium.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-599F.jpg

Boolit deformation between the case mouth and start of throat.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-521F.jpg

Uneven mid-point deformation into the lube grooves.

Uneven retention of lube in the grooves.

Boolit nose slump - that would tend to be uneven.

Flame cutting.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-522F.jpg

Lack of paper patching! :kidding:

There are probably more but why I suggest this type of thing is that the boolit appears to be being launched true but is going off course.

[sagacious]

Since you're using 700X, what is your measured velocity?

If you don't have adequate velocity, your accuracy can be great at 50yds, but terrible at 100yds. That's the very first variable I'd check.

[44man]

Since you're using 700X, what is your measured velocity?

If you don't have adequate velocity, your accuracy can be great at 50yds, but terrible at 100yds. That's the very first variable I'd check.
That is my impression too. Since cast is not shot as fast, the twist could be a little quicker for stability.
That is exactly what happens to my Marlin .44 with the stupid 1 in 38" twist.

[rob45]

That is exactly what happens to my Marlin .44 with the stupid 1 in 38" twist.

I REALLY wish they would change that. Why don't they?? Probably because fools like us keep buying them as is.

[abunaitoo]

Thanks for the info.

Load is 10.5 of 700x.
I really need to get a crony someday.
I'll see if I can figure out a way to catch the bullet.
Public range so there are rules to fallow.

[docone31]

How about that 2A becoming a tack driver at 100 yds with 40.4gns of 4895?
Paper patch it. Wrap it with two wraps, size it to .309. Load and shoot.
No crimp.
Shiney bore as a byproduct.

[sagacious]

Mmmm .... If I may suggest...
Boolit base deformation (feathering at the rifling impressions). This can be determine by low velocity firing into some catch medium.
...
Since the bullet used is a 160gr gas check design, base deformation seems unlikely in this case.

Not preaching, just sayin. :)

[sagacious]

Thanks for the info.

Load is 10.5 of 700x.
I really need to get a crony someday.
...

Your 10.5gr charge probably doesn't leave room for more than a 1gr powder increase with that bullet, but if your recipe and safety allows, up the charge and see if your groups shrink at 100yds.

If your recipe will not safety permit an increase, you may have to go to another powder with that bullet.

There is also a realistic chance that going to a slightly softer alloy, or increasing the sizing diameter (if possible), or using a hotter (non-magnum) primer could help shrink your 100yd groups. This is one of those situations where keeping a reloading log can help a lot when trying to develop accurate loads.

Best of luck! :drinks:

[abunaitoo]

Thanks Guys.

When I worked up the load, I started with 9.0 and worked up to 11.5.
Got the best groups at 50yds with 10.5.
Condom bullets shoot great at 50 and 100yds.
I'll see if a larger bullet will chamber.
If that dosen't work out, I'll try a slower powder.