7mm cartridge choice for long monolithics

[MTMagpie]

Hey all,

New here, new to rifle building, and looking for opinions. I'm planning on building a rifle this winter/spring with the goal of pushing a 177gr Hammer Hunter @ ~3000fps, but I'm really stuck on cartridge and action choices. It's a long bullet @ 1.665"... I had originally planned on doing a budget-ish build on a tikka, but any cartridge capable of what I'm looking for appears to be COAL limited in that tikka-length action/mag. So I'm just looking for some general input, advice from anyone with experience with any of this, or anything really. No matter the action/cartridge, I'll be putting a 1:8 twist barrel on it. I should say, I don't ever plan on shooting factory ammo, only my own loads.

7mm RM - Likely COAL limited in a tikka, otherwise good candidate. Would have to go with a Rem700 clone. Easy to find components. Annoying belt. Hard to rationalize building a 7mm RM with a 1:8 when they're so easy to come by with decent factory barrels.

7 WSM - Might fit in a tikka action? Hard to find components. Short neck is a con.

7 SAUM - Might fit in a tikka action? Impossible to find brass. Otherwise a good choice.

7 SS - Might fit in a tikka action? Brass is actually available! Way bigger startup cost for brass, dies, etc.

.284 Win - Honestly, I don't know enough about this cartridge.

280AI - Likely COAL limited in a tikka, otherwise good candidate. Would have to go with a Rem700 clone. Brass is rare.

28 Nosler - Just too much oomph for me.

7 PRC - Likely COAL limited in a tikka, otherwise good candidate. Would have to go with a Rem700 clone. Still can't find brass. And my ego doesn't want to let me become a f@nboy for a new cartridge.

So if anyone's been down this road or has a suggestion for a cartridge I've missed, please let me know. I'm just having a hard time deciding.

 

[HuntnPack]

7 SAUM. Will work well. Brass is Not hard to find.
It's an over achiever, well designed case, no improvements needed, easy to load for,
easy to shoot. accurate, long barrel life, versatile,
& something you can shoot ALOT.

 

[26Reload]

Well...if'n ya want to go this a different route....I've a AntiX l/a screwed together with a 22" cfproof 65284 that I could pull apart....it would run as a 280ai...box had been lengthened before I bought it...
action is milled liteweight....with 20moa rail.......I'm in se idaho....heading north next month..maybe twice....

 

[elkaholic]

7SS, 7 MAX, or even 7 MEGA everything always in stock.

 

[akmtnhnt]

7 SAUM/7SS will work fine with that bullet on a tikka action. Tikkas are perfect for builds on the short magnums, or anything considered a medium.
7WSM would work to.

 

[MTMagpie]

7SS, 7 MAX, or even 7 MEGA everything always in stock.

Do you think 3000fps is achievable in the 7SS with the 177gr HH or would you step up to the 7 MAX in that case? I guess more is typically better, but I'm still curious . I'm thinking one of these short magnums in a Tikka might be the combo I'm searching for.

 

[JohnnieB]

I shoot the 169 HH's in a custom throated (1/2 regular freebore) 7mm Weatherby, 8 twist. Never tried the 177's. Shoots 1/4 - 1/3 MOA consistently. I love that gun and brass is always available.

 

[elkaholic]

Do you think 3000fps is achievable in the 7SS with the 177gr HH or would you step up to the 7 MAX in that case? I guess more is typically better, but I'm still curious . I'm thinking one of these short magnums in a Tikka might be the combo I'm searching for.

180 Berger will reach 3000 at near max pressure in a 26" barreled SS. Never tried the Hammer? The Max likely would be a safe bet and the mega will run a 180 to 3200

 

[akmtnhnt]

180 Berger will reach 3000 at near max pressure in a 26" barreled SS. Never tried the Hammer? The Max likely would be a safe bet and the mega will run a 180 to 3200

The 177HH is even longer than the 180 Berger VLD. I think it'd depend on how he has the barrel chambered. He'll need to seat it pretty long to maintain the case capacity.

 

[Justice1327]

7 SAUM brass is available frequently.
7 Mega will fit in a Tikka with that bullet.
In my XM +, I get 3105 in a 26" barrel.

 

[Lefty7mmstw]

7rum, 7stw... either will fart that pill out at 3K fps with no effort...

 

[MTMagpie]

I'm leaning toward the 7 SAUM, 7 SS, or 7 MAX at this point just from the standpoint of being able to fit it into a Tikka action. Didn't realize 7 SAUM brass was readily available, though I honestly didn't look to hard.

I'll probably run a 22" barrel to run it with a can in the future. That probably pushes me toward the 7 MAX to make up for the lost velocity in barrel length. Can 7 MAX brass be found fully formed or does it still require some fire forming? Fire forming's not a deal breaker, but it's really nice not to have to do it!

 

[elkaholic]

I'm leaning toward the 7 SAUM, 7 SS, or 7 MAX at this point just from the standpoint of being able to fit it into a Tikka action. Didn't realize 7 SAUM brass was readily available, though I honestly didn't look to hard.

I'll probably run a 22" barrel to run it with a can in the future. That probably pushes me toward the 7 MAX to make up for the lost velocity in barrel length. Can 7 MAX brass be found fully formed or does it still require some fire forming? Fire forming's not a deal breaker, but it's really nice not to have to do it!

7 max is ready to load, fully formed

 

[Northkill]

I'm leaning toward the 7 SAUM, 7 SS, or 7 MAX at this point just from the standpoint of being able to fit it into a Tikka action. Didn't realize 7 SAUM brass was readily available, though I honestly didn't look to hard.

I'll probably run a 22" barrel to run it with a can in the future. That probably pushes me toward the 7 MAX to make up for the lost velocity in barrel length. Can 7 MAX brass be found fully formed or does it still require some fire forming? Fire forming's not a deal breaker, but it's really nice not to have to do it!

If I was you and running a heavy Hammer, I'd really look at the 170 gr HHT. The velocity looks acheivable. The 177 gr requires a 7.5 twist.

.284 Cal-170gr Hammer HHT™ - Hammer Bullets

AT THIS TIME TIPS ARE CONSUMER INSTALLED TIPPING BLOCK INCLUDED WITH EACH ORDER Designed for a minimum twist rate of 1-8", this pure copper lead free Hammer HHT™ will be a great choice for long range hunting with the big 8" twist rifles.

hammerbullets.com

.284 Cal-177gr Hammer Hunter - Hammer Bullets

THIS BULLET IS NOT RECOMMENDED FOR HUNTING BELOW 2500' ELEVATION DUE TO IT'S VERY LONG LENGTH CAUSING DYNAMIC STABILITY ISSUES Minimum required twist rate is 1-7.5" or faster Bullet length is 1.665" Bullet weight is 176 grains Recommended use: Big game hunting G7-BC=.313 estimated

hammerbullets.com