Ultralight Ultralight Rifles

[KyleR1985]

For those doing the 6x45... is there a source to find the 95tmk bullets? Or is everyone just planning on using the 87vmax?

That said, I need someone to talk me into the 6x45 as a better alternative to my 223wylde with the 77tmk. My 16 inch barrel gives me about 2750-2775fps depending on whether it's cold or hot outside. The bullet doesn't drop below 2000fps until 450yards, and doesn't drop below 1800fps until 580 yards. With a 100 yards zero, At 450yards I get 8 inches drift in a full value 5mph wind, and 40 inches of drop.

Is the 6x45 going to push the 87 or 95gr fast enough to beat my 77tmk?

I have a few hundred of the 95tmk’s. I worked with @Taudisio to get an idea of what the cartridge can do with them in his 6x45.

Yes, it will, or at least be very close. This is at 2.37” COAL with windowed mags.

Sierra is supposedly running the bullets in December, available January.


Based on what I’ve seen, I’d feel comfortable with the 87gr vmax or 6mm NBT’s from the cartridge at the distances I’d need. The TMK just stretches that for me - icing. And .243 state legal.


I was pleasantly surprised how easy the 6ARC extracted the other day. That would be the only thing slowing me on the 6x45 train.


I’m getting a barrel either way.

 

[KyleR1985]

I got to 2700 with the 95tmk in 16” 6ARC with lever at mag length. I’ll see what I can get at 2.35” next range session as well. Can probably squeeze a little more out of it. I have my 16” .223 at 2750 with the 77tmk at 2.35”.

@Taudisio can chime in but I believe he got 2600+ with the 6x45. Not sure which powder. At 2.37”.




I also don’t want ULUL, I just want UL. So the extra weight that comes along with the 6mm is ok with me.

 

[goalie]

I got to 2700 with the 95tmk in 16” 6ARC with lever at mag length. I’ll see what I can get at 2.35” next range session as well. Can probably squeeze a little more out of it. I have my 16” .223 at 2750 with the 77tmk at 2.35”.

@Taudisio can chime in but I believe he got 2600+ with the 6x45. Not sure which powder. At 2.37”.




I also don’t want ULUL, I just want UL. So the extra weight that comes along with the 6mm is ok with me.

Is this in a Solo 300 build?

 

[StupidLightweight]

Here’s my take. There’s two reasons to go 6x45 over .223. 1) legality in certain states. 2) increased performance from sub-16-inch barrels. That’s it.

No animal will know the difference. Put bullet in vitals, and lights go out in less than 20 seconds.

 

[KyleR1985]

Here’s my take. There’s two reasons to go 6x45 over .223. 1) legality in certain states. 2) increased performance from sub-16-inch barrels. That’s it.

No animal will know the difference. Put bullet in vitals, and lights go out in less than 20 seconds.

Nailed it.

I will have one or both of these uppers in 10-12.5” builds before it’s over with.

 

[KyleR1985]

Is this in a Solo 300 build?

No.

 

[packgoatguy]

So

Here’s my take. There’s two reasons to go 6x45 over .223. 1) legality in certain states. 2) increased performance from sub-16-inch barrels. That’s it.

No animal will know the difference. Put bullet in vitals, and lights go out in less than 20 seconds.

So, you figure in a 12 inch barrel, the 6mm loses less velocity than the 223? A short barrel ulul is next on my list...

 

[StupidLightweight]

So
So, you figure in a 12 inch barrel, the 6mm loses less velocity than the 223? A short barrel ulul is next on my list...

Case size being equal, the bigger the bore diameter, the more efficient the cartridge will be in a short barrel. Examples: 338 Federal is more efficient than .308, 6.5 CM is more efficient than 22 CM, .30-06 is more efficient than .25-06, etc.

 

[Taudisio]

For those doing the 6x45... is there a source to find the 95tmk bullets? Or is everyone just planning on using the 87vmax?

That said, I need someone to talk me into the 6x45 as a better alternative to my 223wylde with the 77tmk. My 16 inch barrel gives me about 2750-2775fps depending on whether it's cold or hot outside. The bullet doesn't drop below 2000fps until 450yards, and doesn't drop below 1800fps until 580 yards. With a 100 yards zero, At 450yards I get 8 inches drift in a full value 5mph wind, and 40 inches of drop.

Is the 6x45 going to push the 87 or 95gr fast enough to beat my 77tmk?

I’ll let you crunch the numbers, but I don’t think you will gain anything going to the 6mm over the 5.56mm distance wise. I like that it’s a little different cartridge, I get a little more lead to break up/do damage, and it’s legal for elk if I choose to carry the rifle. It was fun researching loads from decades past and seeing lots of old TC pistol data and antelope kills.
I got the 87gr up to 2775 IIRC with a .400 g1
I got the 95gr up to 2664 with a .490 g1

The 87gr load is really stomping on the gas though. My average in my current load is 2715ish average with a higher spread than preferred, but the accuracy is there out to 400 yards. I have not tested the 95gr for accuracy yet, I’ll blame the busy holiday season for that.

The NBTs that I tried must have a longer bearing surface and I wasn’t able to get the velocity to weight ratio anywhere close to the 87gr vmax.

2625 if my hopeful goal with the 95gr. Gets to 1800fps at 500 yards at sea level, 600 yards at 6000 feet.
At 0 elevation it’s 8.2” at 5mph and 46.8” drop.

 

[BREAKCONTACT]

I’ll let you crunch the numbers, but I don’t think you will gain anything going to the 6mm over the 5.56mm distance wise. I like that it’s a little different cartridge, I get a little more lead to break up/do damage, and it’s legal for elk if I choose to carry the rifle. It was fun researching loads from decades past and seeing lots of old TC pistol data and antelope kills.
I got the 87gr up to 2775 IIRC with a .400 g1
I got the 95gr up to 2664 with a .490 g1

The 87gr load is really stomping on the gas though. My average in my current load is 2715ish average with a higher spread than preferred, but the accuracy is there out to 400 yards. I have not tested the 95gr for accuracy yet, I’ll blame the busy holiday season for that.

The NBTs that I tried must have a longer bearing surface and I wasn’t able to get the velocity to weight ratio anywhere close to the 87gr vmax.

2625 if my hopeful goal with the 95gr. Gets to 1800fps at 500 yards at sea level, 600 yards at 6000 feet.
At 0 elevation it’s 8.2” at 5mph and 46.8” drop.

Have you messed with the 90gr eld-x yet?

 

[goalie]

Solo 300 being delivered tomorrow, so I can finally get my Shaw barrel into action. I found about a billion Sierra 77g match kings in my reloading stuff, not the tipped, so I'll use those to practice.

 

[Taudisio]

Have you messed with the 90gr eld-x yet?

Negative. Advertised bc is .409 vs the 87 vmax at .400
I don’t think a guy would be able to tell much of a difference except one tip is slightly more red. That said, I haven’t bought any to play with.

 

[BREAKCONTACT]

Negative. Advertised bc is .409 vs the 87 vmax at .400
I don’t think a guy would be able to tell much of a difference except one tip is slightly more red. That said, I haven’t bought any to play with.

What all ones have you shot with? I'm trying to armchair min/max possible combos while I wait to hear back if someone can buy a 6mm max or 6mm mongoose in a pencil profile barrel from their respective mfgs.

 

[Rams horns]

Sako carbonlight, 5 lb 3 oz, incredible rifle but expensive

 

[gtriple]

Sako carbonlight, 5 lb 3 oz, incredible rifle but expensive

Sweet rifle, but not ultralight. My UL AR build is 3.1lbs for under $1300, not including suppressor, ammo, and optics.

 

[Taudisio]

Sako carbonlight, 5 lb 3 oz, incredible rifle but expensive

4lb 13oz scoped, suppressed, loaded with 10 rounds.

 

[Taudisio]

What all ones have you shot with? I'm trying to armchair min/max possible combos while I wait to hear back if someone can buy a 6mm max or 6mm mongoose in a pencil profile barrel from their respective mfgs.

I’ll have to check my reloading book, NBT 80 & 90, Speer spbt, 95TMK, 87vmax. I have a lot more on my desk to play with. I’ve cut a bunch of the 6mm bullets to compare as well.
My issue with the NBT’s is their advertised BC’s are a lot lower than the Hornady and sierra’s and the velocities I was able to get.

 

[Ferrulewax]

Sweet rifle, but not ultralight. My UL AR build is 3.1lbs for under $1300, not including suppressor, ammo, and optics.

Ultralight, just not ULUL.

On that note, Backpackers have loose weight parameters for Lightweight, UL, SUL and XUL:

“Lightweight (LW) = base weight less than 20lbs.
Ultralight (UL) = base weight less than 10lbs.
Super Ultralight (SUL) = base weight less than 5lbs.
Extreme Ultralight (XUL) = base weight less than 3lbs.”


As fellow gear nerds I think we need similar parameters for rifles. Here are my thoughts for empty rifles but including all accessories and a magazine.

Lightweight= <9 scoped and suppressed
UL= <7 scoped and suppressed
SUL or ULUL= <5 scoped and suppressed
XUL= <3 scoped and suppressed? Maybe 4? Probably only attainable with an SBR or pistol and the lightest of sights unsuppressed.

Of course suppressors are optional, but they definitely need to be part of overall weight because they are a large factor in the system.

 

[gtriple]

Scoped, loaded, bipod, etc. Should include every single item that is dedicated to your shooting system in your rifle weight. If you have a 5lb rifle and a 5lb bipod attached, that's a 10lb rifle....

Plus, 223 ammo is half the weight of a 6.5PRC

 

[Trackselk]

@Ferrulewax
If my math is correct, your XUL would be possible to do suppressed with a 1oz red dot. Maybe even a 16" barrel if you got crazy with skeletonizing the upper, mag, lower etc. Good thing I need more range than those tiny red dots afford, otherwise they'd probably put me in an institution...