Anyone have COALs for their Howa mini?

[grayfox]

Has anyone done any COAL measurements for their Howa mini?
I've seen some load testing but don't recall any COAL results...
Might be of interest since several are coming on-stream now.
And it would give others a useful reference point.
Best ones would be those limited to mag length... just sayin' b/c you can certainly single load but those are more of a specialty type round.

[LRRPF52]

Looks like 2.320" max internal raw COL at the top of the mag.

I saw Grayfox's numbers and thought he must have gotten a different mag, so I went back and measured, and his numbers match mine.

[grayfox]

Well.... I asked the question but then after a bit I figured why not do some measuring myself.

Here's my initial measurements, while I'm waiting for the loktite to set up.
Measuring the internal of the mag gives me 2.322", I would say the max should probably be limited to 2.320" to give you a little space. Now this is for the top two rounds, I assume it's straight-wall all the way down but I did not pack it 5-deep for this part. I was able to fit all of my rounds into that 2.320 limit in the top 2 mag spots. For now I only have the 1 mag.

I didn't do complete COAL measurement to the lands b/c I don't have that equipment, but I do have a bullet seater, calipers, and a collet puller (the collet puller for this type of activity, gents, is THE BOMB! for getting your bullets back, don't go kinetic - get the collet and don't look back!!!).

These are more like go-no go tests but they work for me - my goal is if I can seat the rounds basically the same as I do for my alpha G65 (AR), then I'm happy. Exceptions for a longer seating may come in the future but for now, I wanted to see what this little howa can do.
I used new Hornady brass with a neck rounding and a slight inside VLD chamfer. The first bullets I seated started out at ~2.38-2.40, and they wouldn't go. The 123sst in fact stuck slightly and I had to tap it out - it wasn't stuck very deeply, came out fine.
All of the rounds from then on I limited to the 2.322 +/- max.
These were the ones I checked and the results.

1. TNT 90 - 2.286 was a go, but this bullet ought to be seated deeper b/c it's pretty short. Even 2.250 would be fine for my purposes.
2. Vmax 95 - my original: 2.288-2.290 both were go, however at the range 2.243 failed to load. Back on the bench even 2.164 failed to load; I think b/c the vmax shape looks "fatter" and shorter in its point-to-ogive, than the 123sst.
3. 123sst - 2.322 was a go.
4. 125 Nosler Partition - 2.299 was a go. At 2.321 it actually was pushed in by the barrel to 2.317 but came out easily, didn't stick.
5. 129 sst - 2.320 originally seemed "go" but in the field 2.260-2.250 failed to load.
6. 129 ABLR - this one was a go at 2.318 for me.

My conclusion is... revised: I'll need to re-check and re-verify, esp for the 95 vmax and 129sst.

As a footnote, I had troubles getting the ABLR to work for me in my 65G-AR I think because of its long length... 1.350 vs 129sst at 1.319. the 129 sst shoots pretty well in the AR (I call it the Alpha since it's my first 65G build) with cfe223 at 30.1. (Revised...)
As always do your own testing on your setup, ymmv is the rule of the road.

[grayfox]

My new Howa mini - 20" HB; Boyd's (Correction) pro varmint stock in coyote.
Buckmasters (old style) 4.5-14 SF scope.
Voodoo Innovations MB.


20170727_65Howamini-1.jpg

20170727_65Howamini-2.jpg

[kiwi shooter]

I run 2.200 with seirra 100gn varmint loaded longer at 1st but i was getting contact with the lans
The bullet has a short stubby tip so could load longer if useing something more streamlined still plenty of room in my mag

[smcdurmon]

I've measured my Howa Mini HB Grendel for 2 bullets so far. Will start working on some loads whenever my Dies come in this week.

95gr Vmax - 2.230" Max C.O.A.L
100gr Nosler Ballistic Tip - 2.290" Max C.O.A.L

[grayfox]

I had some time at the range for more breakin, and found my 95 vmax's at 2.243 failed to load in my Howa (now that I have it back from the GS). I edited the post above. Back at the bench 2.243 down to even 2.164 failed to load. Must be b/c the form factor for the vmax is stubbier than the 123's.
Also, at the bench, dummy rounds of 129sst failed to load at 2.260, down to 2.252. So those measurements in the earlier post also seem to be too long. Edited that data above also.
I may need to, for now, use the 90 TNT's instead of the vmax's for this rig. This is a similar conclusion that I reached for my 6.5 SS-18" AR (GrendelHunter); TNT's work fine at 2.180 but vmax's I was afraid were getting too short. Maybe later I might try vmax's below 2.180-2.170.

[grayfox]

AUGHHHhhh!!!

AUGHHHHHHHHH!!!!!!!!!!!!!!! (To quote Charlie Brown)
I have been snookered by the simplest of traps!!! ( at myself!)

It's not about coal, but headspace.
Something just didn't sit right in all of this chambering/not-chambering, so I kept on tinkering...
Turns out the earliest measured coal's were with new brass, that's why they worked at those cartridge lengths.

but if I tried to load my resized/reloaded AR-brass it won't fit in the Howa chamber---> the shoulder is not bumped back far enough!!!! Loads fine in the AR (wonder of wonders!!)...
Shoulda known..... 2 different rifles, 2 unique chambers!!!

The rounds that wouldn't chamber were 2x fired from my AR, and my sizer die is set to bump shoulder back for that chamber about 0.005...
To about 1.219 (hornady comparator B). It works for that gun.
But the Howa needs to be < 1.216-1.2165... and sure enough when I zoomed in (with aging eyes!!!) to the shoulders of the rounds that didn't chamber, there are stress marks on the case/shoulder edge and the slightest hint of a "buckle" - slightest hint, can't feel it but I can see it. I didn't try to force anything too far when chambering.
Howa-fired 1x brass is 1.214-1.216 after firing/before sizing.
AR brass is 1.221-1.222-even sometimes 1.224 after firing/ before sizing.


So... took some 2x brass out of my AR and sized it down to 1.212 (my new setting to use for the Howa)... VOILA! it chambers just fine. (overall length was 1.517-1.520 after sizing.)

So.... here's me with egg ALL OVER my face. (No emoji that I can find, o well!!)

My apologies to the horde!!! Maybe someone else can learn from my most elementary of mistakes.

[kiwi shooter]

Try winding the die down till it touches the shell holder and then size a case and try to chamber if its still to tight go another 1/4 turn so the press actually clicks over center

[LRRPF52]

AUGHHHHHHHHH!!!!!!!!!!!!!!! (To quote Charlie Brown)
I have been snookered by the simplest of traps!!! ( at myself!)

It's not about coal, but headspace.
Something just didn't sit right in all of this chambering/not-chambering, so I kept on tinkering...
Turns out the earliest measured coal's were with new brass, that's why they worked at those cartridge lengths.

but if I tried to load my resized/reloaded AR-brass it won't fit in the Howa chamber---> the shoulder is not bumped back far enough!!!! Loads fine in the AR (wonder of wonders!!)...
Shoulda known..... 2 different rifles, 2 unique chambers!!!

The rounds that wouldn't chamber were 2x fired from my AR, and my sizer die is set to bump shoulder back for that chamber about 0.005...
To about 1.219 (hornady comparator B). It works for that gun.
But the Howa needs to be < 1.216-1.2165... and sure enough when I zoomed in (with aging eyes!!!) to the shoulders of the rounds that didn't chamber, there are stress marks on the case/shoulder edge and the slightest hint of a "buckle" - slightest hint, can't feel it but I can see it. I didn't try to force anything too far when chambering.
Howa-fired 1x brass is 1.214-1.216 after firing/before sizing.
AR brass is 1.221-1.222-even sometimes 1.224 after firing/ before sizing.


So... took some 2x brass out of my AR and sized it down to 1.212 (my new setting to use for the Howa)... VOILA! it chambers just fine. (overall length was 1.517-1.520 after sizing.)

So.... here's me with egg ALL OVER my face. (No emoji that I can find, o well!!)

My apologies to the horde!!! Maybe someone else can learn from my most elementary of mistakes.

I found that I have to size fired AR brass down .006" shoulder relocation to get it to fit in all my AR15 Grendel chambers, as well as my Howa. If it's only sized down .005", it won't chamber in any of them.

I'm also using the Hornady comparator with the B .350" insert for correct shoulder datum location.

[grayfox]

I re-checked the pdf I have of the Saami specs for case and chamber, believe I downloaded it from the forum in April.
What's interesting is that the headspace dimension (with the circle-x) in the Saami pdf using the 0.350 comparator, the chamber dimension seems to be 1.2201 min and 1.2301 max. (and as an aside, the case dimension is 1.220-0.007)
I'm not complaining at all, but it does seem as though the howa's chamber HS doesn't quite have that much. It's more like 1.217 or maybe 8... I don't recall all of the case length trials I tried in sizing-down the case-shoulder, but I'm fairly certain my 1.219 cases wouldn't chamber but the 1.2165 would.
At this point honestly I can live with the howa chamber as is I think, I just might keep "howa brass" length sizing as well as "AR-length" sizing.
Still thinking on it,
I have a Grendel Hunter that may have chamber dimension very close to the Howa's... so like I said, at this point I think I can live with the setup.

update 907 pm: I found my go/no-go gauges, and (as I expected) the howa passes the go gauge check fine. A little tight getting it in there but it's all good... Not worried about the no-go.

[grayfox]

Thanks Kiwi, actually I don't set the die down to touch the shell holder, I'm trying to not work the brass any more than necessary, and going all that way down will cold-work the case more than needed. I aim for a shoulder setback in the 0.004-0.006 range. But your point about the press handle "camming over" is still an accurate observation, if you don't feel that little "camm-push-bump" right at the end of the stroke then you haven't bumped the shoulder at all. And when I first tried the "bolt-fired" brass, my original sizing die setting (for my AR) wasn't giving me that little bump. So point well taken there. That was another clue to me that for the howa my AR setting wasn't a proper setting for die-sizing length for the howa.