Speed needed, moly, HELP!

[roughneck]

Hey folks,

Sorry I'm trying to reinvent the wheel here, but I am soon to receive my custom .243 Win (Kampfeld) with a 1:9 Krieger barrel.

What is my ceiling on bullet weight?

I'm thinking I can run 105 A-MAX bullets at best, but I'm probably going to play it safe with the 90 gr. moly scenar.

Also, why can I push velocity more with moly than with the standard scenar?

Is it a slickness issue? Does a clean pass mean less pressure?

HELP!!

Don't get me wrong...I'm a .5", one hole guy with several rifles...I just don't know a thing about the 243 or moly.

Texas

 

[J E Custom]

Hey folks,

Sorry I'm trying to reinvent the wheel here, but I am soon to receive my custom .243 Win (Kampfeld) with a 1:9 Krieger barrel.

What is my ceiling on bullet weight?

I'm thinking I can run 105 A-MAX bullets at best, but I'm probably going to play it safe with the 90 gr. moly scenar.

Also, why can I push velocity more with moly than with the standard scenar?

Is it a slickness issue? Does a clean pass mean less pressure?

HELP!!

Don't get me wrong...I'm a .5", one hole guy with several rifles...I just don't know a thing about the 243 or moly.

Texas

With a 1 in 9 twist you should be able to shoot up to about 118gr bullets with no problems.

As to the molly, it reduces pressure with the same powder charge so normaly you have to
increase the powder charge to increase velocity.

The best thing to do to get more velocity is to keep the barrel very clean.( Fouling will slow
the bullet down and rough the barrel ).

The Custom barrels are a cut above in the velocity department because of bore finish.

The down side to moly coated bullets is that it is hard to remove an may slow the break in
of the barrel. So break it in using standard bullets ( About 20 rounds with a cleaning between
each shot for 10 rounds and then every 3 shots clean ).Take care of that new barrel and it
will take care of you.

Just my opinion

J E CUSTOM

 

[MagMan]

With a 1 in 9 twist you should be able to shoot up to about 118gr bullets with no problems.

JE, are you sure?? I think you may have an extra 1 in there.

 

[roughneck]

Thanks,

But I don't really need help learning how to break in a barrel.

Also, I clean after every shot for the first twenty, and I shoot them all into the dirt so that I don't get a bad first impression of the barrel.

But, you are saying that moly does reduce pressure? So I can add more powder with moly than with a standard copper jacketed bullet?

Texas

 

[liltank]

Yes, you can use more powder safely. Again safety is the key and walk it up slow. Start at max and go from there. 6mmbr has some good load data for the 6 mm round. I personally like the 243AI.

 

[davewilson]

i'm with Mag, the 9 twist and 105's are about tops. the 115's are pretty much an 8x thing. i've never tried the 115's with my 9x. have heard from more than one it won't work.

BuffaloBob has a Weatherby and shoots 115's but i think his is an 8x. maybe he'll jump in.

 

[J E Custom]

i'm with Mag, the 9 twist and 105's are about tops. the 115's are pretty much an 8x thing. i've never tried the 115's with my 9x. have heard from more than one it won't work.

BuffaloBob has a Weatherby and shoots 115's but i think his is an 8x. maybe he'll jump in.

Most of the model 70 winchesters in 243 were 1 in 10 twist and they shot the 100+gr bullets
fine but the 6mm remingtion came out with a 1 in 12 twist an the winchesters spanked there ***
and thats why the 243 became so popular.

A faster twist is recomended but the question was if his barrel would shoot a 105 gr A Max
and I think it will.

All rifles like certain bullets and the only way to find out is to try them.

Most of the people on long range hunting like faster twist and most bench rest shooters like
slower twist. so there is no fast and hard rule about twist rates only recommendations.

J E CUSTOM

 

[roughneck]

JE,

Thanks for the insight.

I think that the premium barrel will allow me to squeeze out 105s also.

Now, with the moly issue... Can I reasonably shoot moly bullets of the same weight faster than standards?

TX

 

[liltank]

Technically yes. You have to load higher pressures to achieve the velocity you are looking for, however this is due to the coating. Some people have had to crimp the necks to A) hold the bullets in when casing are loaded to make volume, and B) to get the pressures necessary. Its a trade off. Regular bullets higher pressures at reasonable loads, or higher velocities and more powder required.

 

[jwp475]

If you are at max speed and pressure with a non Moly bullet and then you load and shoot Moly bullets with the same amount of powder you will get less speed and it will take more powder to get the same speed as the un coated bullets. I do not think that you will be able to get more speed than an uncoated bullet simply because the case will run out of room to add more powder

 

[BountyHunter]

Most guys that are coating bullets have left moly and gone to the boron nitride. Lot easier to put on the bullets. Go to BR central and 6mmbr and search for articles and info.

You can also send the barrel off and have a melonite coating put on it. Article on www.6mmbr.com on that. Joel Kendrick is top 600 yd record holder has over 5000 rounds thru his gun using melonite and it is a wildcat which is basically a 6x44. He is reporting no erosion and faster speeds.

With a 9 twist you can also go to the BIB flat base bullet which is a 108. He also has a 118. I have been running the 108s at 3130 fps in a 6mmBRDX (ack Imp) in a 9 twist. Randy Robinett (6mmbr and BR central) is owner of BIBs and can answer on the 118 in a 9 twist. The FB bullets can be run faster with less pressure in the 9 twists compared to the 8 twist.

bh

 

[roughneck]

To all,

I'm confused... why is george garland getting 195 fps more with moly in the same bullet (115 dtac)???

He's using way more powder though... so back to the original question... can I run moly boolits faster than standards??

Tex

 

[jwp475]

If you run them faster you have to generate more pressure, there are no free lunches

 

[pressman]

In my experience you really don't gain much with moly and if you are not familiar with it. it will frustrate you. one thing is for sure if you clean your barrel completely it will take 2 or 3 shots -- to recoat the inside of the barrel with moly to get the groups back. and you will not get more speed just because it is moly coated. you will get less if you use the same charge. however with moly you can get by with more powered due to the less pressure that the moly bullets create.
Now back to this George thing. Are you using the same kind of powder and the same charge?? even the primer? and is his barrel the same lenght? and his barrel cut rifled or button. As far as speed goes their are several things that can make 100 fps differance. Even the condition will make some differences. Each thing i have mentioned could effect speed a just a couple together would get you 100fps one way or the other.
My big question is if your gun will really shoot a certain load don't worry about 100fts just know your gun. dial it in and kill it. 100 fps is not noticable until you get out past 300 yards or so.