New build...7mm LRM or 7-338 Norma?

[KPK]

Thinking about starting to collect parts for a new project.

What's your thoughts on the two cartridges? Wanting to run the 180-200g bullets to 3000+ For hunting etc.

Stick with the LRM in a normal long action and less recoil or step up to the 7-338 Norma in the LM action? How much more recoil and rifle weight could be expected?

 

[garandman]

I just had a 338 Norma built. Not sure what a 7-338 Norma is...

 

[Bluejazz]

I just had a 338 Norma built. Not sure what a 7-338 Norma is...

It is called a 284 JAZZ. (7-338 Norma AI)

 

[Bluejazz]

Any cartridge based off the 338 Norma is going to have alittle more case capacity than the 7 LRM or the 7-300 WM..
not sure if it is necessary for what you want to do. You will have to decide.

 

[Sharp Shooter]

I have a 7-300norma improved. I can launch a 180 Berger at 3500fps. Great cartridge. Shot lots of 10 inch 5 shots groups at a mile. Shot an elk last year at 1380 yards. I would suggest a 30 inch barrel with this case. 42 MOA to a mile.

 

[KPK]

I'm really think may as well go for it and do the larger of the two. Have a couple 7mm saum and more speed would be nice.

Sharp Shooter, I'm not real familiar, but isn't the .300 norma just a necked down .338 norma? If so did you base yours. Off of it for ease of brass making by just necking it down to .284?

Who built it? How/where did u get dies, and how hard is it to form/make brass?

I'm thinking tac338 action, mcmillan a1-3, medium Palma at 28-30", etc......

 

[tui_man]

I have a 7-300norma improved. I can launch a 180 Berger at 3500fps. Great cartridge. Shot lots of 10 inch 5 shots groups at a mile. Shot an elk last year at 1380 yards. I would suggest a 30 inch barrel with this case. 42 MOA to a mile.

That's hauling arse!!!
What load etc do you run?

I have made a few on Remington actions etc for hunting rifles so are 26" barrels an they get the 180gr hybrid 3300fps
Mines a 7mm-338 Norma mag imp to 40* an minimum case taper.
They run around 98-101gr of US869

That's it on the left.
7mm screamer
6mm x 47Lapua
7mm gonzo (7mm-300 Blaser mag imp to 40º an minimum taper)
Is around the same is the 7mm LRM an 7-375r
162 a max 3300-3350fps
180 hybrid 3150-3200fps

 

[Sharp Shooter]

Tom Sarver of ThunderValley Precision built my rifle for me. He has the reamers and the dies. Tom calls the cartridge 7mm Hulk. If you want to step it up a bit Tom also has a 7mm Thunderhawk. It's based on a 408 cheytac case which is shortened and necked down to 7mm. I have the 300 thunder hawk. Which is the same thing only 30cal. I can shoot the 215 Berger 3600fps. I have only shot this round to a mile never put it on paper. One day at the range in perfect conditions I hit the 10 inch by 10 inch steel target 8 times in a row. Tom and my self were shocked. I probably could of hit the target more but I ran out of bullets. If you are considering building a 7-300 Norma I would build it with a minimum of 30 inch barrel. I use H-1000 powder in mine. I use the 300 Norma brass for ease of forming.

 

[bodhisafa]

^^^
Could you share more information on the 7mm hulk you mention. There is not much info on the TVP website on this calibers.

I'm interested in a new 7mm

 

[KPK]

1:9 twist at 28-30" enough on the 7-338?

 

[KPK]

180 or 195 if they ever come out.

 

[Sharp Shooter]

What I know about the cartridge is back in the late 1990s Tom Sarver was a 1000yd benchrest shooter. He competed with Dave Tooley cartridge called the 300 yogi. Which was a 338 Lapua with a tight neck necked down to 30 caliber with a 40 degree shoulder. Tom competed with the 240 grain SMK. He felt the cartridge was not efficient so he shortened the case and necked it down to 30 cal and improved the case which he called the 300 Hulk. Tom ended up shooting the 1000yd world record with a 1.???? 5 shot group and a perfect 5x 50 score. One to Two years later Norma came out with the 338 Norma case which is the same dimensions only they changed the case taper and shoulder angle. So instead of using a 338 Laupa case and shortening the case and necking it down to 30 cal or 7mm you can use a 338 Norma case or a 300 Norma case and neck it down to 7mm fire form it and you will have a 7mm Hulk. Hope this helps.

 

[turbo54]

[MENTION=17174]Sharp Shooter[/MENTION]

I believe Tom Sarver's cartridges are called "Hulk" and "ThunderHulk".

Anyway, his wildcats are well designed and perform nicely. They're also highly overbore, but he does a ton of fiddling around with different ideas and designs.

I know I'd certainly choose the 7mm-338NM improved (aka 7mm Hulk) if I wanted a ridiculous but "almost" reasonable 7mm magnum.

The 7mm ThunderHulk though... Jesus H Christ that thing is off the charts ridiculous. I believe he claims 17moa @ 1760 yards.

 

[bodhisafa]

Twist rate?

Barrels life expected?

For this hulk...

 

[turbo54]

Twist rate?

Barrels life expected?

For this hulk...

1:9 is plenty, 1:9.5 will be ok.

Not too long.

 

[Sharp Shooter]

I would guess 1500 to 2000 rounds. I have 842 through my rifle right now.

 

[18Echo]

A 7-300WM will get your 180's above 3150 without the need to do anything special to the case beyond necking it down to a 7mm, how much speed do you really want/need?

Search for SkyKings post on this sight for info on his 7-300WM, and look over on Longrangehunting.com's forum for about a 68 page thread on the 7-300WM. Unless your just into obscure wildcats (which I get) and lots of brass prep (which I don't) the 7-300WM is the way to go.

 

[flims]

A 7-300WM will get your 180's above 3150 without the need to do anything special to the case beyond necking it down to a 7mm, how much speed do you really want/need?

Search for SkyKings post on this sight for info on his 7-300WM, and look over on Longrangehunting.com's forum for about a 68 page thread on the 7-300WM. Unless your just into obscure wildcats (which I get) and lots of brass prep (which I don't) the 7-300WM is the way to go.

How fast can the 168 and 180 bergers be driven to maintain F Class worth accuracy? When I was discussing this with the guys at the nationals they told me that occassionally guys running 7 WSMs face issues with this as their 180s would not always behave reliably past 3150.

What sort of reliability and performance do you get when you are pushing these bullets at +3200? It's cool in numbers but this it hold water?

tnks

R

 

[ZLBubba]

A 7-300WM will get your 180's above 3150 without the need to do anything special to the case beyond necking it down to a 7mm, how much speed do you really want/need?

Search for SkyKings post on this sight for info on his 7-300WM, and look over on Longrangehunting.com's forum for about a 68 page thread on the 7-300WM. Unless your just into obscure wildcats (which I get) and lots of brass prep (which I don't) the 7-300WM is the way to go.

^This. My 7-300WM is at 3190 fps with 180gr (pointed) Hybrids, 26" barrel. That's like 5.8 mils to 1k and almost 2000 yards supersonic. Not bad at all.

 

[18Echo]

^This. My 7-300WM is at 3190 fps with 180gr (pointed) Hybrids, 26" barrel. That's like 5.8 mils to 1k and almost 2000 yards supersonic. Not bad at all.

What powder are you using.... I'm guessing Retumbo or H1000?

 

[ZLBubba]

Retumbo. I've got some H1000 that I use in my 300 WM, but Retumbo's the ticket for the 7-300WM.

 

[Weaselthis]

Bubba, not to hijack the OP (he might be interested in the info as well), but would you care the share your load for the 180's & Retumbo? I've got a new 7/300WM bbl. coming from GAP soon. The old 26" Remmy bbl. maxed out at 74g H1000 and 3050fps w/ the 180g Bergers. Hoping to increase that w/ a 28-29" and either H1000 or Retumbo. Looking forward to trying the 175 ABLR's as well. If you would rather not, understandable, perhaps you could pm me? Thanks in advance.

Retumbo. I've got some H1000 that I use in my 300 WM, but Retumbo's the ticket for the 7-300WM.

 

[ZLBubba]

Bubba, not to hijack the OP (he might be interested in the info as well), but would you care the share your load for the 180's & Retumbo? I've got a new 7/300WM bbl. coming from GAP soon. The old 26" Remmy bbl. maxed out at 74g H1000 and 3050fps w/ the 180g Bergers. Hoping to increase that w/ a 28-29" and either H1000 or Retumbo. Looking forward to trying the 175 ABLR's as well. If you would rather not, understandable, perhaps you could pm me? Thanks in advance.

I'm traveling right now but when I get home , I'll send you a PM. I know you know this, but back off my loads at least 10% and work up. I don't know which reamer GAP uses but the LRI reamer is snug. The 7-300WM is a sweet round. I hope you find a great accuracy node at the right speeds.

 

[Weaselthis]

Thank you sir! Appreciated. No hurry. Rifle still being worked on. And yes, I DO know to start low and go up instead of start high and go low....lol

I'm traveling right now but when I get home , I'll send you a PM. I know you know this, but back off my loads at least 10% and work up. I don't know which reamer GAP uses but the LRI reamer is snug. The 7-300WM is a sweet round. I hope you find a great accuracy node at the right speeds.

 

[bjay]

i was about to build 7-300wm then i start reading rbrothers about 7mm rogue..ill be waiting for this cal..launching 180 in 3300? how many barrel life are we geting? are you guys shooting 2 miles?

 

[flims]

Can the 180s take this kind of velocity past 3100?

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