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308kiwi

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About 308kiwi

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  1. 308kiwi

    Subsonic suppressed 308AR

    Yeah I know, gives a good reference as to how quiet it is though
  2. 308kiwi

    Subsonic suppressed 308AR

    Yep, couldn't agree more, The lightest I load now for 308 is 175gr, have boxes and boxes of 135, 155, gathering dust. I have a mate who swages projectiles as a bit of a hobby business, the lightest .30 he makes is 165gr, he's trying to source longer jackets at the moment so he can get into the 200+ range.
  3. 308kiwi

    Subsonic suppressed 308AR

    Here ya go, 10 rounds of 190gr sub sonic 308, averaged 1019fps over the chrono, and as you can see the bolt locked to the rear on the last round, the brass was almost in one little pile about 5 feet away from me PSD brass, Fiocchi large rifle primers, 10gr IMR Trail Boss 190gr Berger HPBT Had to do nothing to the lower, ie has the same 308 buffer and spring that I have been using for both my 308 and 243 uppers, BCG is std Aero M5. The barrel, like I posted at the beginning of this thread, 14", 1:10 twist, std 308 chamber, pistol length gas tube fitted into a Syrac adj gas block, (that I haven't had to adjust, it's fully open), gas port is at .110" Target is seven rounds @ 50yards. This is seriously fun to shoot, lovin it
  4. 308kiwi

    Subsonic suppressed 308AR

    IT WORKS, just put 40 rounds through it, cycles and locks the bolt to the rear on last round, I am soooooooooooooo farkin excited, almost no recoil. I've run out of loaded ammo, couldn't help myself shot it all before I thought to grab a camera, about to go and load some more up, will try to get some video footage tomorrow and post it. Oh boy this is going to be a fun toy.
  5. 308kiwi

    Subsonic suppressed 308AR

    I have been seriously looking at the 375 Raptor as well. If this project doesn't work out I will have a spare BCG, Upper, barrel extension etc in need of a new barrel.............Hmmmmmmmmmm
  6. 308kiwi

    Subsonic suppressed 308AR

    Yeah, I've considered that, every load is going to be printed before the suppressor gets screwed on, do not need to be tumbling bullets sideways through an expensive suppressor. Am going to start with 200gr, but I've got a decent selection of .30 bullets ranging from 135gr to 220gr to try. My barrel is 1:10. Good points dpete, I'm leaning along the line of thought that it is pressure that I need rather than a quantity/volume of gas, and like has been discussed, a given weight projectile needs x amount of pressure to drive it at x velocity, so from that, I already know from experience that Trail boss can easily drive 175 to 200gr projectile to 1050 fps, (in a bolt rifle), so must be generating the same amount of pressure as any sub sonic load in 300 BLK, or any other calibre for that matter, that is achieving the same results. Hence my decision to go with a pistol length gas system and a 14" barrel, giving as much exposure of that pressure to the gas system for as long as possible, like I said, that combination of gas port location vs barrel length seems to work well with 300 BLK, the only reason Trail boss isn't used in 300 BLK is that the bulk density of the powder is so high that you simply cannot get enough of it in a 300 BLK case. If I get some spare time this month it will all be academic cause I'll know if it cycles or not and rest assured I'll be posting it here.😃 FWIW, these guys are doing it using 220gr projectiles and loading 14.5gr of IMR4759 powder which is pretty close to H110 apparently, I just do not want to be dealing with the hassles of loading such small amounts of powder and the inherent problems that come with that. https://www.youtube.com/watch?v=rYGrAsCRWTs
  7. 308kiwi

    Subsonic suppressed 308AR

    It should pretty much be the same I would have thought, given projectile at a given speed and spin should perform equally. I'm sure I'll be advised by some at some stage as to why I should have just built a 300 BLK upper......yep, fair comment but I want a quiet 308, I already have everything I need to make subsonic 308 ammo, have been loading it for years for bolt guns. We have a big problem with feral goats over here and you have to 'quietly' shoot them cause as soon as they think they are in danger they are gone, I think this will be just the ticket for shooting these pests.
  8. 308kiwi

    Subsonic suppressed 308AR

    Trying to decide on where to go with the gas system has been a mission, pretty much came down in the end to replicating the AR15 300 BLK system that by all accounts gives the most reliable cycling with subsonic AR15 300 BLK loads, from what I found a 14" barrel with a pistol length gas tube seems to give adequate dwell time for 190-200ish gr projectiles being driven by sufficient gas pressure to keep them sub sonic but still cycle the rifle, I figure I'm doing nothing different except I have to drive a heavier BCG and recoil system, so this is where the specific suppressor comes into play, the design of the chambers is such that the gases are 'trapped' in the suppressor longer than a std baffle type design, I'm relying on this to boost the BCG via these gases escaping back down the barrel and giving the BCG a helping hand, 'delayed semi blow back' if you will, after all, this very phenomenon is what gives the accelerated BCG velocity in suppressed AR15's and 308AR's. And if that all fails then I'll machine up a lightweight buffer and start playing with AR15 carbine springs to build a recoil system that replicates 300 BLK AR15 but behind a 308 BCG. Now the suppressor has turned up I'm all motivated again to get this thing running, stay tuned
  9. Have had this project on the go for a while, dedicated subsonic, suppressed, 308 upper, not even sure it's going to work yet but you never know until you try :-) Finally after 6 weeks and dealing with translating Swedish to English and back to Swedish paperwork, my new suppressor turned up today, Over barrel Aimsport Triton 42S, made in Sweden. I'm particularly intrigued with the concept of this design, no baffles, instead it uses 3 large expansion chambers (I guess you could say it does have baffles, just not in the sense we are familiar with in suppressor design). Barrel is 14", 1:10 twist, just need to cut the chamber, set head space and assemble it into the upper. Mate of mine swaged me some 200gr projectiles to try, IMR Trail Boss powder, has proven itself well in the past with subsonic bolt rifle loads. Will post up some more when I get it all together and see what happens
  10. 308kiwi

    Weather

    I'll swap any of you lot, it's friggin 35C, (95F) here today, this pasty white boy is melting.
  11. 308kiwi

    Pictures of Glock’s

    Picked this up a couple of weeks ago, 19X. had no intention of buying another Glock let alone one in 9mm, but it just feels and points so damn nice I had to take it home.
  12. 😁 I still remember how the world was going to be changed forever by all the 'short' and 'super short' magnums that came out in the 90's and early 2000's.
  13. 6.5 CM is all anyone has been talking about over here for the last year or so, I just don't get it myself, perhaps it's because I drink my coffee without sugar and the blacker the better and my idea of 'hairstyle' is a #2 crew cut. Could also be because I'm past 50 and have seen all these so called wonder calibres before...........now get of my fukin lawn...... Sorry for hijacking your thread carverelli Nice rifle, post up your results.
  14. H4350 is made by ADI in Australia for Hodgdon, ADI call it AR2209, it's a very popular powder here, especially in the likes of 243 Win, 260 Rem, 7mm-08 and now the hipster 6.5 CM, I guess it would also perform well in the latest wonder, 6mm CM I use it in 243 Win and 6mm Rem, it's my 'perfect powder' for these calibres 😀
  15. 308kiwi

    Completely Off-Topic

    We were there October 2016, the whole rear of the flight deck is a space museum, the shuttle, a lunar capsule, heaps and heaps of stuff from the space program, just so cool to see it all close up.
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