My thinking is that the short chambered barrels will have to be recalled and corrected.
There can't be two standards for the ammo makers, one for in spec barrels and one for the short throated ones.
If in spec ammo is causing possible safety problems in the short throated barrels they won't limit all future ammo to accommodate for that.
Not sure what to think about this barrel, the UPS guy just dropped off 200 rounds of Hornady 108's. I took measurments of the round and 20 out of 20 in the box measured 2.245-2.246, pretty consistent measurments.
These rounds chamber and eject just fine, so the problem seems to only be with the 105's. But what I can not figure out is why my hand loaded 108's would stick in the chamber. I need to take some more measurements between factory and my loads. The ones I loaded were with Hornady 108 grain ELD's which is the same bullet that comes factory loaded.
I would like to see if other folks with other brand barrels have the same problem with the 105's, I heard initially that the problem was across the board with all barrels. That is why Hornady changed the COL of this particular round. I have 1000 of these bullets but really don't want to load any of them until we have more info on them. then again I have plenty of 108's to get me through untill they release the new fangled bullets.
When I get my proof bbl assembled, probably next week, I'll check the 105's. I'd guess the 108 have a longer taper so their oal might be fine. 105 a bit more stubby as it were.
I may have stumble upon a fix for the 105 grain bullets. I have some Nosler RDF bullets the G1 is .571, so these are extremely efficient bullets. .But they have a longer taper to them over the Hornady bullet. I opened up my calipers and stuck the bullets in the gap hitting the olgave, the Nostler bullet protruded about .020 longer than the Hornady.
I got a similar result comparing the 105 hpbt to the 103 eldx (the one I hope to use).
I measure the ogive for 105 at 0.602; and the 103 eldx at 0.650. From base to ogive on each is basically equal, using my calipers and the case mouth of a 6 CM as the ogive "marker."
By the way, looking at these and the case size, and the saami chart, it appears as though the whole intent of these long-for-caliber bullets is to seat well into the throat/ lands area (though I'm sure, not touching).
07-31-2020, 11:50 PM (This post was last modified: 07-31-2020, 11:55 PM by Dino11.
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(07-31-2020, 11:06 PM)grayfox Wrote: I got a similar result comparing the 105 hpbt to the 103 eldx (the one I hope to use).
I measure the ogive for 105 at 0.602; and the 103 eldx at 0.650. From base to ogive on each is basically equal, using my calipers and the case mouth of a 6 CM as the ogive "marker."
By the way, looking at these and the case size, and the saami chart, it appears as though the whole intent of these long-for-caliber bullets is to seat well into the throat/ lands area (though I'm sure, not touching).
Yep, short lead jump and as much of the bullet in the rifling as you can get without pushing the bullet into the land. A compressed load and a high BC bullet and you have all the requirements for an ultra high efficient round. Tim at Hornady told me I will be super impressed with the capabilities of this round. It is truly a sniper round good to 1000+ yards with ex stream accuracy. And I would bet that the DoD is using this for just those reasons. The military needed a multi purpose sniper rifle that could be carried easily in the field and used for long range targeting, as well as short range use in a light weight package. Factory rounds are going to show no justice to this platform. My results were nothing short of steller, but I think that their is more room for improvement in the roll your own crowd.
(08-02-2020, 12:02 AM)grayfox Wrote: Hope howa or somebody gets into the bolt game for us budget-guys, lol!
Gotta be a nice rig.
Let us know how it shoots.
I haven't decided for sure, but I think I'm gonna hold out for a Howa HB 20"...or a Lilja AR740. One or the other
I just returned from initial break in of my 20" faxon barrel with the 105 factories, and this was a good day! the cartridges load/unload without a hitch, and avg of my first ones under chrony were 2694, SSD 15. All shots locked back fine. 1 group of 3, 0.919"/100 yds, sd group 0.2" (3) and 1.06" (4) for 100 yds. 11 shots downrange in it.
08-07-2020, 11:09 PM (This post was last modified: 08-07-2020, 11:11 PM by Dino11.)
I just got my Faxon barrels, the 20" came yesterday and the 18" today along with another 200 rounds of 108's that I ordered from GA Precision a couple of days ago, that was fast shipping.
Tomorrow I am going to get the tools out and measure the chambers on all three of my barrels and compare them. I have to go to Kromehard. It's a tool store that specializes in drill bits, machinist tools, taps and dies, ect... I need a 5/16 36 tap so I can make a 6 Arc modified case, as non are available.
My range trip today was pretty good as far as accuracy, all 100 yard targets were well below MOA, I have not measured them yet but was putting holes inside of holes. One target that I put 20 rounds into the whole center of the target inside of an MOA was gone. Ringing steel at 600 with ease.
I figured out my lock back issue, and short stroking, it was the adjustment on the gas block, all is good now with those issues.
I'll report back with what I find out about chamber dimensions. I needed a fired case to make the tool with.
