Thread: Kiwi made Howa mini ultralight chassis a reality?

That photo has my loins twitching.

Ah man I was so happy with my current .223! These look absolutely amazing man! So stoked they are kiwi made too!

@Wingman, would it be possible please to describe the build of your rifle and the various lightening steps necessary from normal (if any) that gives the stated 1.6kg weight, assuming already that that figure is without bipod, scope and rings?

Originally Posted by Puffin

@Wingman, would it be possible please to describe the build of your rifle and the various lightening steps necessary from normal (if any) that gives the stated 1.6kg weight, assuming already that that figure is without bipod, scope and rings?

Hey mate, yes correct, bare rifle weight, without going into to much detail, grams add up to kgs... I really pushed the boat out on my personal build.
The base production chassis that is available is 510gr. My one is a little lighter at 488gr as it has a few custom built prototype parts on it such as the cheek rest and mount and a few hollow drilled parts.
FYI the same chassis in magnesium instead of 6061 T6 alloy weights 382gr.

The barreled actions vary in weight depending on chambering, barrel length, material and barrel profile.. here is a std heavy barrel blued 16.5" .300blk and and a std S/S 20" barrel lightweight 6.5 Grendel on the scales.





My Grendel started as the lightweight S/S model. It has a smaller knox profile and lends itself to a much lighter build. My barrel has been cut back to 10.5" re-profiled and carbon fiber tension sleeved. It now weighs 394 grams. The bare s/s lightweight action is about 360gr from memory but I dont seem to have a photo..



My bolt knob has been removed and replaced with a carbon one which shaved another 7 grams.







All the bolts on the rifle (102gr) have been replaced with titanium bolts (46gr).
All my accessories are also lightweight options:
I run the shorter DPT Mini over barrel suppressor with 2 baffles. 200gr instead of 285gr for the std DPT.



The already light Talley ultra low rings have been machined/ hollowed out on the underside shaving a few more grams... I run a very minimalistic M-loc bipod, and a compact scope.
There are lots of other small things that shave very small amounts of weight but this all removes from the total weight.

I want one of these chassis for my rem700 sa!!

Originally Posted by Chur Bay

Picked my new rig up today.
Attachment 211048

Looking good @Chur Bay ...
That's about as minimalist as it gets.
With a set-up like that you can't be much over 2kg ready to go?

A light weight 6mm arc please.

6mm BR please

Originally Posted by Gkp

A light weight 6mm arc please.

That my thinking too. 1/10 twist 16" barrel for the lighter projectiles. Like under 90 grains.

Originally Posted by DeonK

That my thinking too. 1/10 twist 16" barrel for the lighter projectiles. Like under 90 grains.

Why on earth would you want a 6MMARC with a slow twist? Its only efficient with the heavier projectiles and you can fire 80 grain projectiles through a 1 in 8 twist fine but not 108/110 through a 1 in 10.

Because i can and i don't agree that it only effiecient with with heavier projectiles. Each to their own mate. Someone on here( forgot his name) got one and he knows what he talking about.

Also i already got a 1/8 twist which i want to keep as it is.

While 6mm ARC has some benefits with a long barrel shooting 100-110gr bullets it is pretty limp wristed with a short barrel which I designed this chassis to be used with.
Ideally a 12.5 inch barrel is where this chassis shines to keep it compact and light without loosing its knockdown power in the Howa mini chamberings.
I have built a few 6mm ARCs and they have nothing on a 6.5mm Grendel with a short barrel. The Grendel runs the higher BC 123gr bullets with the option of running 130gr or even 140gr if you wanted more energy.
6mm Grendel can spice up the ARC a bit and can be made with a Grendel bushing neck die with a 6mm bushing.
6mm AR turbo 40deg for the speed chasers.
6x45 is better for the slower twist lighter 6mm bullets but in general the 6mm range need a 20" to 24" barrel to get performance to match the 6.5 grendel.
6BR or 6mm Dasher are possible built on the .450 bushmaster bolt face. Whether or not the mini action with its smaller bolt lugs are designed to cope with these higher presuered cartridges is debatable.

Thanks for the very imformative explanation @Wingman. Food for thought.

Originally Posted by Wingman

...but in general the 6mm range need a 20" to 24" barrel to get performance to match the 6.5 grendel...

Hmmm... Not so sure about that mate.

What velocity can you achieve out of the 12.5" Grendel barrel? Not a ragged edge figure, a kind to brass no pressure kind of figure.

Haven't got the figures in front of me, but IIRC the Quickload models were very anemic. Like 2100-2200 ft/sec MV.

Whilst I get the weight / portability bonus, a 20" 6mm barrel in 6mm XC / Creedmoor etc is going to be carry way more energy downrange with the 108gr ELD-M for example.

My 22" 6mm has almost double the energy of a 12.5" Grendel assuming a 2,300 ft/sec MV for the Grendel, which is probably generous. And the Grendel performs considerably worse in windage as well. If I were to shorten my 6mm barrel to 16" I'm pretty confident I'd be seeing an MV around 2,700 ft/sec, which still significantly outperforms the Grendel down-range.

So unless I'm missing something here, there's pretty major trade-off in killing power going for the mini-action / short barrel package.

Would be good to hear your views on that.