6mm GT vs 6mm CM for next rifle build

[Brandon_SPC]

First of all thank y'all for dealing with my indecisiveness on my next rifle build and cartridges but I think I have narrowed it down to the caliber. I'm just going to stay with the 6mm since I already have a 6mm ARC. It makes sourcing components easier (bullets and primers). My next build is looking to be as follows:

Action: Probably a Kelby Nanook. If not it will be a lightweight SA in that weight range
Barrel: 18" Carbon from Preferred Barrel Blanks 1:7
Scope: Probably the NF NX6 2.5-12
Stock: Peak 44 Blacktooth
Suppressor: Airlock 6.5
Rings: Ruffs Precision (I got these on my Howa Mini and like them so far)
Bottom Metal: Hawkins Precision R700
Trigger: TriggerTech Special.

The rifle should be just shy of 8lbs outfitted. My goal with this rifle is to keep it between 7.5-8.5lbs. Mainly to have a nimble hunting rifle that isn't a pain to shoot. Still able to spot impacts to some extent, able to take anything in the lower 48 just fine, but also forget it is there when I am hiking up the mountain.

I really would like to shoot the 116 TMK from this and would like to hit at least 2600 fps MV. This should still put me at 1900 fps impact velocity at 500 yards around sea leavel (where I live) and plenty where I normally elk hunt. Is this doable with the 6mm GT or do I need to step up to the 6mm CM?

I really do appreciate everyone's input.

 

[Hondo64d]

How much freebore and what’s your max length for your chosen magazines? Which one will let you reach the lands at magazine length?

John

 

[khuber84]

A 169 freebore 6gt would be perfect for the 116, the saami 183 6cm chamber will also jive well.

An 18" 6gt will be getting near pressure around 2800 with the best powders, it'll probably shoot there, but I don't like running that close to psi.

A 18in 6cm will give you a 100fps buffer above these numbers.

With your goal, the 6gt will do just fine. However I'd personally be looking at the 107tmk with a 292g7 VS a 116 with 300g7. The speed advantage gained with the 107 in the small case will out out weigh the 116s slight bc advantage. The 107smk would prob be best fit with the 0.120 6gt chamber.

 

[Brandon_SPC]

How much freebore and what’s your max length for your chosen magazines? Which one will let you reach the lands at magazine length?

John

I would be using the standard internal box magazine with a bdl style hinge floor plate. I'm not a fan of magazines for most hunting.

 

[Brandon_SPC]

A 169 freebore 6gt would be perfect for the 116, the saami 183 6cm chamber will also jive well.

An 18" 6gt will be getting near pressure around 2800 with the best powders, it'll probably shoot there, but I don't like running that close to psi.

A 18in 6cm will give you a 100fps buffer above these numbers.

With your goal, the 6gt will do just fine. However I'd personally be looking at the 107tmk with a 292g7 VS a 116 with 300g7. The speed advantage gained with the 107 in the small case will out out weigh the 116s slight bc advantage. The 107smk would prob be best fit with the 0.120 6gt chamber.

10-4. I was looking more at the 116 due to the higher sectional density for hunting. That's the only reason but I'll have me some 107 tmks for my 6mm arc. So I'll definitely give them a try in the GT if I go that route.

 

[khuber84]

I would be using the standard internal box magazine with a bdl style hinge floor plate. I'm not a fan of magazines for most hunting.

Then 6cm is likely the best choice. I don't know of anyone, or saw reports of anyone, running 6gt from a bdl style box mag.

I don't think SD is a worry as even the 95tmk gets excellent penetration and wound channels.

 

[pathnz]

GT feeds fine from a BDL