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(continuation of previous post)
Here is how the modified Grendel bolt and the modified 30rd mag interface:
The 20rd mag, as mentioned, did not need any feed lip modification. Weird.
And here is the whole pistol put together. I may or may not replace the KAK brace, it seems fine for now. I do have a Geissele trigger I am going to try in the KS-47 lower.
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Very cool, Im interested in how it functions and your accuracy with the 6.5 Grendel in the KS-47.
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03-07-2020, 06:31 PM
(This post was last modified: 03-07-2020, 06:42 PM by m796rider.)
I cut down a spare firing pin for function testing to ensure I don't end up dimpling primers.
With that modified firing pin in place, I have now manually run about 6-7 mags worth of Wolf steel cased ammo through the rifle. So far, ammo feeds fine. I can even load the mags to full capacity and not have any issue loading a mag on a closed bolt.
I can also verify actual AK 7.62 mags don't work, as they present the rounds too low for the bolt face to pick them up and feed correctly.
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Quick range report:
The 30 round magazine worked perfectly, no problems at all. The 20 round magazine did not like being used as a monopod -- this caused the feed lips to interfere with the bolt. Shooting standing with no upward pressure on the 20rd mag worked fine. I shot 70 rounds of Wolf steel cased and 6 rounds of Hornady 123gr SST (brass cased, fed fine). No time to do accuracy testing.
The extractor on my Grendel bolt is weak. I will be adding an o-ring to start, and may swap out the spring if necessary.
The best combination of buffer/spring ended up being the AR10-length spring from PSA and a standard carbine buffer.
I've modded the 20 round mag feed lip as needed to allow shooting with upward pressure on the mag. More testing to follow!
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Sounds great thanks for the update.
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This is pretty sweet! Drop a line to PSA on this and see if they have interest in producing it.
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How have the Csspecs mags performed for you guys?
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03-11-2020, 02:47 AM
(This post was last modified: 03-11-2020, 08:36 PM by m796rider.)
Jeff@Evocatus Wrote:How have the Csspecs mags performed for you guys?
After modding the right side feed lips to clear the bolt, mags work 100% in my KS-47. I'm waiting for them to go on sale again to pick up a few more 30 rounders.
ETA: I think I will shave a bit off one of the bolt lugs to better match the 7.62x39 bolt that came with the KS-47 and see if this runs with unmodded mags.
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m796rider Wrote:After modding the right side feed lips to clear the bolt, mags work 100% in my KS-47. I'm waiting for them to go on sale again to pick up a few more 30 rounders.
ETA: I think I will shave a bit off one of the bolt lugs to better match the 7.62x39 bolt that came with the KS-47 and see if this runs with unmodded mags.
I'm reeeeeally curious to see what you would suggest for the final result (mag mod vs. no mag mod).
How did you re-profile the non-PSA bolt? Just filed it down? What about the magazine?
I bought a mag, stripped upper/complete lower and had the same result (getting stuck on the magazine). I was about to abandon the project and just make a 7.62x39 pistol out of it then saw the work you did.
I'm still intrigued, but man i was hoping it would be a lot easier than this!
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AP Smizzlers Wrote:I'm reeeeeally curious to see what you would suggest for the final result (mag mod vs. no mag mod).
How did you re-profile the non-PSA bolt? Just filed it down? What about the magazine?
I bought a mag, stripped upper/complete lower and had the same result (getting stuck on the magazine). I was about to abandon the project and just make a 7.62x39 pistol out of it then saw the work you did.
I'm still intrigued, but man i was hoping it would be a lot easier than this!
I locked a Dremel with a carbide grinding bit into my bench vise and carefully worked both the bolt and my mags against the spinning bit. This worked quite well -- it's by no means as clean as doing work with a CNC machine, but the results are definitely serviceable.
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I have a Devil Dog Concepts Hard Charger and a few more CSSpecs mags coming in... More testing to follow.
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Just Ordered a monster barrel and bolt for my KS build, Thanks for posting pics. I wonder if we could get a better deal on mags if we ordered more together, I only want 3-6 probably (2) 20s and (2) 30s
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Let me know what firing pin you settle on also
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san antonio fj Wrote:Let me know what firing pin you settle on also
So far, a standard AR firing pin has worked great. I'm also using a Geissele SSA trigger, which also works great.
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Extra CSSpecs 30rd mags came in today.
I had to grind down the rear mag latches a tiny bit and push in the rear corners of the top of the mags a tiny bit for solid lockup. No other mods to the mags. Not all that different from what I have to do to some AK mags to fit my AK.
So far they work when hand-feeding rounds. Range time on Monday if all goes well.
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Great work. What fun to have the only KS-47 in the world!
Paul Peloquin
Did government credibility die of Covid or with Covid?
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biodsl Wrote:Great work. What fun to have the only KS-47 in the world!
Hopefully PSA will fix that situation...
I installed the DDC Hard Charger. It's pretty cool and seems to work well. You still have to break cheekweld to charge the pistol but at least you can be in something that approximates low ready.
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OT They also have a short article on The 6mmARC. Nothing new but maybe they can dig some new info.
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AP Smizzlers Wrote:https://www.thefirearmblog.com/blog/2020...-15-build/
Hey man! You're internet famous!
So are you!