7mm X .338 Lapua?

In you guys' opinions, if absolute maximum velocity is not an issue, how necessary is a 28" tube going to be in the 7X.338L? I would certainly prefer a 26" if I could get away with it. Can I switch powder to something slightly faster and run 26" without creating a fire breathing dragon?

With that large of a case capacity you need a longer barrel, even longer than 28 would be a good. When you get powder capacities above that of a 7mm STW, you need to start adding barrel length.
 
Here are some interesting numbers....... for reference only, obviously as some "Improved" wildcat versions may be different from others..... all the case capacities were generated by Quick Design, except for the 7mm LRH which was confirmed with fired cases......

7mm Slayer (7mm/500Jeffery).................................. 141.0 gr
7mm/338 Excalibur................................................. 138.0 gr
7mm/378 WBY....................................................... 130.0 gr
7mm Lazzeroni Firebird........................................... 126.1 gr
7mm/338 Lapua Imp............................................... 120.0 gr
7mm/338 Lapua..................................................... 113.0 gr
7mm RUM............................................................. 112.7 gr
7mm Long Range Hunter... confirmed capacity............... 108.5 gr
7mm/338 Norma Imp variants........................... 106 gr - 108.5 gr
7mm/338 Norma..................................................... 105.5 gr
7mm/300 Norma..................................................... 103.4 gr
28 Nosler Imp 40 *.... my design................................ 102.4 gr
7mm STW................................................................ 100.2 gr
7mm 375 Ruger....................................................... 100.0 gr
28 Nosler.................................................................. 99.6 gr
7mm/8mmX68 S Imp................................................. 99.4 gr
7mm/300 WBY.......................................................... 99.3 gr
7mm Dakota............................................................. 93.5 gr
7mm/300 Win Mag..................................................... 92.4 gr
7mm WBY................................................................. 87.6 gr
7mm Rem Mag.......................................................... 87.0 gr
7mm WSM................................................................ 79.5 gr
7mm SAUM............................................................... 76.1 gr




here is my shameless plug pic .......... fire at will.....

If I remember right, you are pushing a 195 to 3300 with the 7mm LRH? How many firings per case? Any idea on the pressure you are at?
 
Any thoughts on a small caliber 7mm or 30 caliber at extreme long range? Most cartridges for extreme long range 338 Lapua and wildcats, 375 cheytac, 416s and 50s are so overpowered that they would have difficulty with over penetration for hunting inside of 1000yrds.

Regards
 
Any thoughts on a small caliber 7mm or 30 caliber at extreme long range? Most cartridges for extreme long range 338 Lapua and wildcats, 375 cheytac, 416s and 50s are so overpowered that they would have difficulty with over penetration for hunting inside of 1000yrds.

Regards
30 and 28 Sherman Magnum fit the bill pretty well. Std mag bolt face, no belt, reamers, dies and brass in stock.
shermanwildcatcartridges.com
 
Thanks elkaholic, just been looking at 7mm cartridge ballistics it looks like a 197gr Sierra Matchking at 3200fps stays supersonic out to around 2200yrds. By no means a 2 mile KO2M cartridge nessasarily but still impressive.

Regards
 
A 7-338 Lapua Imp is a lot more capacity then a 7RUM. I have the .30 version and I load 112grs of ball powder with a 230 Berger. It would be closer to a 378 Weatherby capacity wise.
I stumbled across this just reading about wildcats, so I know its old. But of course it would be similar to a .378 Wby. Roy took a .416 Rigby and slapped a belt on it and called it his .378.
 
A standard 338 Lapua case is between a 338RUM and a 338 Edge. A improved case is quite a bit more capacity. It's not as much as the 378 Weatherby case but it is close and velocities are comparable, mainly due to the toughness of the Lapua cases. A Norma improved is almost identical to a RUM for capacity but .350" shorter. I have a 7-338 Norma Imp. reamer I just got Monday and have a 7-338 Lapua Imp on order for a customer. I have both of the same cases in .30 caliber.
Hi, recharging this thread. Thinking about building this caliber and getting a reamer with PT&G.

1) Can anyone on here point me to the best custom dies for this caliber?
2) Should I get a blank die from PT&G and have the gunsmith reamer a die while he doing the barrel, or should I fireform rounds and send off to a custom die maker like Whidden? Except, how do I get the initial cases loaded up with 7mm bullets if I did that?
Would love to chat with a knowledgeable person here: 7577016266.
 

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