30/338 Lapua

I've been doing alot of thinking about a big 30cal and it has come down to the 300 TOMAHAWK or the 30/338 Lapua or one of the improved version of it. What I would like to know is what are some of you guys with the standard 30/338 Lapua getting as far as velocity with the 240gr SMK. I will be using a custom action with a 34" barrel, if I can get 3100 fps without improving anything that is what I'd like to do.
Thanks,
Wayne

[Darryl Cassel]

Wayne

You can get 3100 FPS with a standard 300 RUM and 240 gr bullets with that 34" barrel.
You wouldn't have to improve anything.

Later
DC

[Brent]

Wayne,

I know you are looking for all the real world data now, but for what it's worth, I used an OAL of 3.9" for all of them on that LFAD program of mine, with your 34" barrel. All were at 65k psi.

Here's what it came up with...

30/338 Lapua with 240 SMK = 3025
30/338 Lapua with 220 SMK = 3150

30/338 Lapua Imp with 240 SMK = 3100
30/338 Lapua Imp with 220 SMK = 3225

300 Ultra with 240 SMK = 3025
300 Ultra with 220 SMK = 3150

300 Ultra Imp with 240 SMK = 3035
300 Ultra Imp with 220 SMK = 3175

The powder used here was slightly slower burning than the RL25 I've been using, my 26" barreled 300 Ultra is getting 2950 fps with a 220 SMK at a 67,000 psi average. The program predicts a somewhat "optimum" outlook based on you using a pretty slow powder here. At 3031 fps I was up into the 71,500 psi range, factory ammo produces about 62k psi in my gun...

[ 03-02-2003: Message edited by: Brent ]

[Darryl Cassel]

For what's it's worth.

Here are some real world results from a 300 Rum and the 300 Tomahawk while shooting in 50 degree temperature.

I know Boyd was getting over 3100 FPS or 3150 FPS with his 300 RUM with the 36" barrel and my Tomahawk is getting me up to 3235 fps with the 240 gr MK and a 34" barrel.

I have reloaded that ammo 5X so far without stress signs to the case. No extraction problems either.

I use the WC872 powder in mine.

Later
DC [img]images/icons/smile.gif[/img]


Boyd----What velocity were you getting from yours with 240s? I know you mentioned it was 3150 or 3172 FPS now that I think about it.

[ 03-02-2003: Message edited by: Darryl Cassel ]

[Boyd Heaton]

Darryl,My accuracy load is at 3168 with the 240's.I have ran them saftly in MY GUN to 3200....

[Brent]

Darryl,

what is the case capacity difference on the improved version of yours? I seem to only be able to come up with a grain and a half difference no matter how I design the improved cartridge?

On your 338/416, I moved the shoulder forward a full .100" and gained 5.0gr capacity, I would have thought "10.0", but not the case. Your neck on the 338/416 is very long and this was easy to do, with the Ultra's already short neck I'm just not seeing it come even close?

3235 with a 240, that's almost 400 fps faster than my Ultra would likely do at max load and my barrel is just 8 inches shorter, that's 50 fps an inch?

Here's a post of Boyd's I saved from a month ago to work up a 240 SMK when I found some, it seems about right, so I'm totally perplexed here?

Boyd Heaton
One Of Us
Member # 5999 posted 01-20-2003 05:04

Try 178gr A-Max's and 93 to 96gr of RL25 or Retumbo..If accuracy is what you're looking for try 80 to 83gr of RL25 or Retumbo with a 240gr MK....They will be slow....Around 2750 to 2800.

[ 01-20-2003, 05:07: Message edited by: Boyd Heaton ]

--------------------
Boyd Heaton Assistant Pit Chairman.Original Pennsylvania 1000 Yard Benchrest Club

Posts: 354 | From: Pa | Registered: Jul 2001 | IP: Logged

Thanks guys for all your input. I'm still hoping someone out there has what I'm looking for. I'm not yet set on the Lapua case but I like the shorter fat case and the better case of the Lapua. I have 500 RUM cases to work with, might still go with the 300 RUM, maybe the TOMAHAWK but looking for "real world data" on the 30/338 Lapua.
P.S. Boyd, you did an awesome job in the video, keep up the good work! Can't wait for #3.
Wayne

[ 03-02-2003: Message edited by: Wayne McD ]