September 13, 2018, 07:15 PM | #26 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
As for the bergers--I'm guessing they could push beyond 90 if they went to an AR hybrid type design as they've done with other calibers.
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! |
|
September 13, 2018, 08:04 PM | #27 |
Member
Join Date: June 19, 2007
Posts: 39
|
They could but I know what Berger is working on and what Federal will load next year, I just can't say anything yet.
They all know now that the heavy long nosed VLDs are not going to produce the best performance. Lighter faster bullets with a slightly lower BC will out perform the 90gr + because of the extra case capacity from shorter bullets and velocity possible from the lighter bullets. |
September 13, 2018, 10:23 PM | #28 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
I keep forgetting--this is for presumably SAAMI-compliant max COL 2.26 factory ammo I assume.
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! Last edited by stagpanther; September 14, 2018 at 06:31 AM. |
|
September 14, 2018, 11:16 AM | #29 |
Member
Join Date: June 19, 2007
Posts: 39
|
What kind of velocities are you getting from 88s, 90s and 95s? Run those through a ballistic program and then run a 80gr ELD at 3000fps then compare. At first I didn't think there would be that much difference in velocity and the higher BC bullets would overcome but actual field tests are showing something different.
|
September 14, 2018, 01:41 PM | #30 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
I'm only just now starting to test cartridges that I would call "SAAMI-compliant" in your new shorter freebore barrel using conventional magazines and COL's--so I don't have any meaningful data yet. Do you know if these projected performance numbers by the manufacturers are going to be attainable in "conventional" in-spec cartridges? The engineers at Hornady are powder formulation wizards so I wouldn't be surprised if they manage it.
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! |
|
September 17, 2018, 09:51 PM | #31 |
Member
Join Date: June 19, 2007
Posts: 39
|
No, factories wouldn't dare push a 80 to 3000. This is comparing warm handload to warm handload with all available bullets.
|
September 18, 2018, 04:56 AM | #32 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
I see. This sure has been a very interesting ride.
Quote:
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! Last edited by stagpanther; September 18, 2018 at 05:10 AM. |
|
September 26, 2018, 05:11 AM | #33 |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
The plot thickens. I just received notification of this post over on the 6.8forum by Bison Armory (which manufactures and distributes the valk):
Quote Originally Posted by constructor View Post T his is how to check the chamber... The accurate way is seat a 1" long .224 inspection pin in a case out until it touches the lands. From the base of the case to the front of that .224" diameter pin should be 1.676+- a few thou for tolerance. response by Bison Armory: "This is not true. If I've done my math right the real answer for a perfect 0.224 diameter pin, and assuming a cartridge case that has zero head clearance, is 1.6882 to 1.6982 (or 12 to 22 thou greater than 1.676) for a chamber cut to perfect maximum material condition and then those two numbers are for absolute minimum and maximum headspace, so the real answer will be in-between. Actually the real answer will be somewhat longer still because nobody cuts a chamber to minimum SAAMI tolerance. The number will probably be smaller though by a couple thou if you are using new brass instead of fire-formed brass. The OAL for typical chamber dimensions, i.e. ones that are cut 0.0005 greater in diameter than MMC, the length increases for minimum headspace from 1.6882 to 1.6977 and max headspace from 1.6982 to 1.7077. In either situation we're looking at about 22 to 32 thou greater than 1.676, a fair bit more than "a few for tolerance." The actual tolerance for a SAAMI chamber is 0.002" for the diameters, so the .224 diameter pin could result in a substantially longer OAL to the lands in a chamber that is still technically correct and within SAAMI specification. This chamber thing is really getting on my nerves. I have to answer way to many "Are your .224 Valkyrie chambers in spec?" questions every day, and also "My chamber is out of spec because my bullets are seating blah blah blah" based on false information. It needs to stop here." I admit this is way above my pay grade and I don't want to be an instrument of spreading false information--my comments have been specifically related to the the distance(s) forward of the case mouth and the length of freebore to the point where the bore constriction forces the bullet to engage the lands/grooves. I don't know if that issue is implicitly addressed by either the SAAMI spec diagram or the comment above.
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! |
September 26, 2018, 03:54 PM | #34 |
Member
Join Date: June 19, 2007
Posts: 39
|
He'll figure it out eventually just like he changed his 6.8 chamber to one with a shorter freebore like mine after 9 years.
|
September 26, 2018, 04:07 PM | #35 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
I was talking to a custom cartridge manufacturer today and he told me he often gets calls about the mediocre performance of existing valk factory offerings from the bigger outfits.
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! Last edited by stagpanther; September 26, 2018 at 04:24 PM. |
|
September 26, 2018, 04:38 PM | #36 |
Member
Join Date: June 19, 2007
Posts: 39
|
Right, unless the reloader just happens to find the sweet spot in jump length it's tough to get decent accuracy at mag length when the jump is 50+
|
September 26, 2018, 05:03 PM | #37 |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
My word--I just took a glance over there on 6.8--guys really went at it! Why not just challenge him to a shootout to produce the best groups he can with the "developmental" chamber cut and conventional mag length cartridges. I think that 90 vld load I found could be refined a bit
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! Last edited by stagpanther; September 26, 2018 at 05:11 PM. |
September 27, 2018, 02:29 AM | #38 |
Senior Member
Join Date: May 14, 2017
Posts: 123
|
Sweet! How do you like that muzzle brake? I have a 224 Valkyrie barrel for a future project and looked at the muzzle brake.
|
September 27, 2018, 04:18 AM | #39 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! |
|
September 27, 2018, 08:50 AM | #40 |
Senior Member
Join Date: November 5, 2016
Location: DFW, TX
Posts: 1,147
|
Wow, missed that conversation since not active on the Forums lately. The problems and causes of the problem with the cartridge goes over my head and knowledge. But one thing I'm certain of, there's been a problem with this cartridge since the day it was introduced where some have good accuracy but most don't. For someone to say there isn't a problem with this cartridge, just doesn't make sense. Maybe he doesn't get it.
|
September 29, 2018, 10:38 PM | #41 | |
Senior Member
Join Date: March 2, 2014
Posts: 11,655
|
Quote:
__________________
"Everyone speaks gun."--Robert O'Neill I am NOT an expert--I do not have any formal experience or certification in firearms use or testing; use any information I post at your own risk! |
|
Thread Tools | Search this Thread |
|
|