Howa mini-action in grendel to be released in mid-2016

[Matt @ LSI]

Hmm, Howa MA shoot it for awhile and get you a Bartlien or Hawk Hill 22" barrel to replace the factory. Then slowly add new aftermarket parts as they come available.

6.5 TBAC Ultra 7" thing of beauty

@ Matt@LSI what is the diameter of the heavy Barrel or who's contours are you guys using? Thanks and I know I speak for the rest of the fellas it's great to have you here and hope you stay a permanently!

we use a #6 contour for our heavy barrels. so .750" muzzle OD
and thanks! glad i can be of service!

[BluntForceTrauma]

I played with the numbers in the JBM Ballistics Calculator and here is what I got. I input for a 6.5mm 129 Nosler Accubond Long Range (0.553 BC-Litz) and I made an educated guess for a 6.5 Grendel load at 2450 fps in a 20" barrel, 200-yd zero, wind 10mph, target speed 0, all other inputs default. I then bumped it to 2600 fps — increase of 150 fps — for a hypothetical, higher-pressure bolt-action load with all other inputs the same.

300-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 1.3", DRIFT = 0.3", VELOCITY = 134 fps

600-YARD DIFFERENCES BETWEEN 2450 fps and 2600 fps
DROP = 12.3", DRIFT = 2.6", VELOCITY = 116 fps (yes, the gap narrowed)

Only the shooter can say whether the differences are worth it to him.

Full charts attached below. OK, I see the charts imported at very low resolution, barely readable. Anyway, you get my drift. . . .

[adamjp]

If I wanted to hot-rod it in a bolt action to say 60,000psi like a lot of bolt gun rounds are chambered for skip the mini or micro actions for the Grendel and do a build on a Savage or Remington 700, Dakota will build a real sweet Grendel for enough $$$. Those actions can take the added pressure and do with their larger bolt lugs in lots of other cartridges with larger case heads. There are some that are loading the CZ actions hot but I like my gun too much to push it too far, for that in 6.5s there is already a 6.5-284 and 264 Win Mag in the safe. I will take my CZ a bit higher than the max loads for the AR but not much. Just my 2 cents

You didn't comprehend my previous post did you.

It is not the bolt action strength that is the problem, it is the brass. Yes, you can hotrod to 60k PSI (and I'm using Lapua brass which is head and shoulders above anything made in America) but your primers will need superglue to stay in on the third reload. Either that or you can then ream the primer pocket to take a large rifle primer and get another couple of loads out of the cases.

Short version, at 60k PSI the cases stretch quickly across the base which make the primer pockets loose.

[adamjp]

Let me pull down some arbitrary numbers just to help focus the discussion. If we operate under the assumption that Hornady, Lapua, PPU and Nosler 6.5 Grendel BRASS — not talking about AR15 bolt — can easily handle 60,000 psi pressure rounds or whatever they shoot 6mmPPC at, what are the pros and cons of loading to, oh, 58,500 in a new Howa Mini-Action (MA)?

The expectation would be to gain 100-200 fps more velocity. (This assumes the next step up, something like the 6.5 Creedmoor, gains 350-450 fps per bullet in equal-length barrels at about 60,000 psi vs. the 65G. And feel free to question my assumptions! Let's get on the same page — this isn't ARF.com.)

Is this doable in the MA? Doable with caveats? Insane? Let's explore this from a technical perspective.

FFS, ignore the person who has been shooting a Grendel bolt gun for years and make it up as we go.

Grendel brass is NOT PPC brass.
Grendel chambers are not tight match chambers found in PPC.
Grendel reloading dies are not minimum disruption straightline dies found in PPC benchrest.

Grendel cases by Lapua cannot be run at 60k PSI with any expectation of even moderate life.

It has nothing to do with the action and everything to do with the brass.

[BluntForceTrauma]

Adam, please don't take this discussion as a personal affront. I didn't realize your close involvement in this. I read where you've been shooting Howa mini actions for a while; are you saying you've tested one chambered in 65G?

I've never shot Lapua 65G cases at or around 60k psi, but I seem to remember Bill Alexander saying they could handle it and were top quality in line with the rest of Lapua brass. I could well be wrong; I'd have to ask him again, but he'd be a good source since he, along with Janne Pohjoispää then of Lapua, designed the case.

Your experience in this matter is very valuable, so what is your basis for saying 65G Lapua brass is not rated for 60k?

[Matt @ LSI]

i guarantee that NO ONE has tested max pressure of a mini action besides the factory. ONCE AGAIN, we DO NOT recommend pushing the limits of any cartridge beyond what is SAAMI spec. To retain the warranty, factory ammunition must be used. I cannot tell you how many instances we have had with people and their hand loads. Be safe, as noted by Bluntforcetrauma, what do you really gain by the added pressure?

[Drift]

Ahh... I'm OK with getting 3 loadings out of my brass..if it gives me the performance I want.
I have no way to test the pressure of my handloads. With my CZ527 and the Grendel, when I start backing out primers, I call that the max loads then I back down .2 gr . I figured out a long time ago that it was a dumb idea to publish those loads here. Still and all, we ought to get better velocity out of a bolt action than a AR.

[adamjp]

Adam, please don't take this discussion as a personal affront. I didn't realize your close involvement in this. I read where you've been shooting Howa mini actions for a while; are you saying you've tested one chambered in 65G?

I've never shot Lapua 65G cases at or around 60k psi, but I seem to remember Bill Alexander saying they could handle it and were top quality in line with the rest of Lapua brass. I could well be wrong; I'd have to ask him again, but he'd be a good source since he, along with Janne Pohjoispää then of Lapua, designed the case.

Your experience in this matter is very valuable, so what is your basis for saying 65G Lapua brass is not rated for 60k?

Basis? How about a few years of shooting Lapua 6.5 Grendel brass in a bolt action (NOT a Howa Mini as they are not yet available). When I got my Grendel I tried a number of different loadings, some of them well over the design pressure. I didn't pop primers, but I have a dozen cases on their fourth reload that don't hold a primer any more. These cases are now givaways to collectors or Grendel fanciers who want a dummy case for reference.

My frustration is down to repeatedly stating that the brass is the limiting factor and yet y'all keep running down the 'we need a bigger action' route. If you want the higher velocities, get a bigger case.

You have made some assumptions that since the Grendel is derived from the PPC and that from the 220 then 7.62x39 that the Grendel brass is built the same as the 6mm PPC case. I have owned rifles in both cartridges and whilst the exterior dimensions of the head are the same, the internal construction isn't. The head also appears to be softer than the Lapua high pressure brass (220 Russian, 6mm BR, 6.5x47 Lapua and 6.5x284).

I don't pretend to know what the Grendel brass was originally specced for, but I suspect that it was designed for the target rifle - the AR15. The SSAMI specification appears to be 52k PSI (average) which makes 60K PSI a significant overload. A pressure rating of 52k PSI will work nicely in a 50k PSI action such as that found in the AR15. Stoke it to 60k PSI in an AR15 and the action will let go, but in a (good) boltgun like the Howa Mini the action will work well (their design failure is possibly in the 70 to 80k PSI range like most bolt actions) however the brass becomes the weak link in the system as it will still stretch and fail quickly with repeated loadings.

My hunting load is a 100gn NBT or TTSX over 31.5gn of BM 8208 (IMR 8208XBR in the USA) which delivers 2980fps out of the 21in barrel of my Zastava m85 based rifle. It is probably quite warm, dancing at the 55k to 58k range (sadly we have noted before that Quickload does not seem to model the Grendel very well at all) but is all-year capable (temperatures range from -5 to 35 deg C). I note that the Hodgdon load data for the same load is maximum at 30.8gn and 2730fps from a 24in barrel at 47,600psi, some on this forum have gone further in their AR15s, and others have noted bolt failures too.

As LRRP has noted, don't chase velocity. Chase accuracy and let the bullet BC do the job - even the 100gn bullets really do work well.

[BjornF16]

IIRC as I was researching hand loads for my Grendel bolt, 58k psi was the number I ran across as max for the brass.

When I did my workup with Hornady 129 Interbonds (see https://www.dropbox.com/s/45bfe3ki85fpx7...ksheet.pdf), I closely monitored brass, primers and velocity as I exceeded Grendel AR max with CFE 223.

I've pondered using Federal GM small rifle primers versus CCI 450 small rifle magnum primers. What do y'all reckon the difference would be?

Edit: Chronograph used was Chrony Beta Master; AA brass was Lapua.

[Doon]

I found that changing to a federal 205 SRP from a Win SRP closed up my groups as per pic.
The load was 31.5 gn CFE-223 Hornady brass 123gn SST @ 2.280
Both loads are the same apart from the primer, I repeated this a few times to be sure.

It was in a Savage Grendel LBC .264 20.5" Barrel with suppressor.

[BjornF16]

I found that changing to a federal 205 SRP from a Win SRP closed up my groups as per pic.
The load was 31.5 gn CFE-223 Hornady brass 123gn SST @ 2.280
Both loads are the same apart from the primer, I repeated this a few times to be sure.

It was in a Savage Grendel LBC .264 20.5" Barrel with suppressor.

Good to know; cheers for that Doon.

[BluntForceTrauma]

Bill Alexander texted back with some info. I quote:

"Draw and heading dies are .220 Russian. Only the final draw, necking, and taper dies are different."

"Case has been tested to run safely at 58,000 psi and can be reloaded. Proof loads run at +67,000 psi."

"All the margins from the SAAMI max are to provide safety."

"Howa's action is adequate for the SAAMI spec, but this is not a full-blown benchrest rig. It will come unglued if pushed."

[BjornF16]

Bill Alexander:

"Case has been tested to run safely at 58,000 psi and can be reloaded.

"Howa's action is adequate for the SAAMI spec, but this is not a full-blown benchrest rig. It will come unglued if pushed."

Like I said, 58k psi is what I found when researching my loading for my bolt action. For a hand loader, I'd prefer a short action.

[usmcm16a2]

Folks,


My local FFL spoke with LSI today, and my HWA60603 is on order!!!!!!. 22 inch #2 contour green stock. The waiting begins, A2

[Doon]

Reply from Matt@LSI, thankyou

Re: Grendel Throat
good morning,

the Howa factory cam back with an answer, .300 throat

[LRRPF52]

Bill Alexander texted back with some info. I quote:

"Draw and heading dies are .220 Russian. Only the final draw, necking, and taper dies are different."

"Case has been tested to run safely at 58,000 psi and can be reloaded. Proof loads run at +67,000 psi."

"All the margins from the SAAMI max are to provide safety."

"Howa's action is adequate for the SAAMI spec, but this is not a full-blown benchrest rig. It will come unglued if pushed."

Another thing with bolt guns is that if you experience a lug failure, you get to eat a bolt through your face, which can and has been fatal. With the AR15, the blast goes down the mag well most of the time, unless you're really brave/stupid, and you fragment your bolt carrier and upper receiver outwards.

[BluntForceTrauma]

My local FFL spoke with LSI today, and my HWA60603 is on order

Are you able to share the street price?

[Matt @ LSI]

Another thing with bolt guns is that if you experience a lug failure, you get to eat a bolt through your face, which can and has been fatal. With the AR15, the blast goes down the mag well most of the time, unless you're really brave/stupid, and you fragment your bolt carrier and upper receiver outwards.

so a few features about the Howa bolt.
2 locking lugs
3 pressure vent holes in the bolt body
forged one-peice bolt and handle (not brazed on or welded like some companies)
bolt handle itself acts as a third locking lug when closed.
m16 style external extractor and internal plunger ejector.

the receivers are also forged one piece flat bottom receiver with an integral recoil lug. these things are over built in comparison to some other bolt gun offerings.

[LRRPF52]

so a few features about the Howa bolt.
2 locking lugs
3 pressure vent holes in the bolt body
forged one-peice bolt and handle (not brazed on or welded like some companies)
bolt handle itself acts as a third locking lug when closed.
m16 style external extractor and internal plunger ejector.

the receivers are also forged one piece flat bottom receiver with an integral recoil lug. these things are over built in comparison to some other bolt gun offerings.

That's good to know. My plans are to start my kids out on the Grendel once they go center fire rifle, beginning with reduced loads and light pills.

[blackhog]

Matt @ LSI,
Welcome and hope you stay permanent. Y'all are on a long and profitable path with a mainstream 6.5G bolt gun. Just get them out in hands of shooters and the sales will speak for themselves that an extensive aftermarket product line is necessary. 2 items that should be marketed first, quality replacement stocks and a scope mounting system that will work with the Mini Action and different eye relief distance scopes. IMO