M*CARBO Brotherhood

Non firing Sub 2K after upgrades

So I installed my all-in-one upgrades and now it will sometimes fire. I don’t know why it will work and then not work. I guess I’ll have to reopen it again. Sigh.

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@ADiesel44 First, welcome aboard. I’m not familiar with the Sub 2K, but FTF is usually a failure to go into battery and/or a firing pin/light strike issue. Good luck, hope you get it sorted.

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it happens. watch the videos, and make sure you have everything positioned and locked in like it is supposed to be. dont fire any more to you reassemble, you could damage parts.

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it is definetly tricky getting everything back just right and took me about 2 hours the first time I did it, there are a couple of springs that do not want to stay put and you have to watch them and sometimes hold them in place when doing the reinstall of parts, I recommend taking it apart again starting from scratch and build it back up, after that contact a gunsmith or KelTec?

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@ADiesel44 welcome to the forum anthony

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Thanks for the insight. I was dreading reopening the sub but it was a lot easier (& faster) the 2nd time. When I reopened it, the hammer spring wasn’t seated quite where it was supposed to be. I double checked everything and is now dry firing everytime. Next stop, is the range!!!

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that’s great to hear that you were able to figure it out! and get everything working right keep us updated when you hit the range!

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Went to the range last week. The new flat trigger and all the upgrades felt great. Sub is back in action, and better than ever. Took a couple of friends who had never shot a sub. We all enjoyed a nice day at the range.

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I just installed the pro kit last week and at the range today had 3 light-strike FTFs. It sounds to me like the lighter hammer spring is too light. Everything is installed and working correctly and I used a liberal amount of PTFE on the hammer pin, sear, and trigger pin - nothing is hanging up.

The primers have obvious shallow indents from the firing pin and 2 out of the 3 fired when tried again. The last had to be tried 3 times before it fired. Going back to the original hammer spring won’t be a problem - before installing, trigger pull was only 5lb 9oz and afterwards dropped to 4lb 6oz - I can live it.

Is light primer strikes using the lighter hammer spring common? Any way to resolve this without using the original spring?

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I should have added that I was using Winchester white box. I’ve shot 400-500 rounds of it through this weapon without a single misfire, jam, failure to feed, etc.

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do you mean sometimes the trigger reset and sometime it doesn’t? happen to me once and some pin was messed up

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Everything is working correctly, the trigger resets fine. I polished everything to mirror brightness - hammer, hammer pin, sear, sear pin, trigger bar, trigger bar pin, trigger pin, feed ramp, and chamber - and coated anything that moved with PTFE.

The hammer doesn’t seem to be striking hard enough. I can understand one, maybe two light strikes but three… I was using the same ammo from the same lot I used the week before with no misfires. There are dimples on the primers where the firing pin hits but they aren’t deep enough to fire the cartridge - the last one took three tries. I’m going to reinstall the original hammer spring and try again this weekend. It’s too bad teardown is such a PITA. :grimacing:

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@phuzzy42 Try pulling the firing pin out and check the spring. Clean all the gunk off of it and the firing pin channel. Put it back together dry, no lube. Hope this solves your problem Steve.

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The only oil I use is a couple drops of CLP where the bolt and bolt head hook on each other to lube the tube a little, nothing on the bolt face. I use Action Blaster on the bolt face itself and in the firing pin channel - it’s clean and dry, the spring is good, and the extractor is clean. Thanks for the suggestion, though.

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I fully expected mine to do nothing but click when I pulled trigger. Mine worked fine and it surprised me. Unfortunately, that doesn’t help you. Sorry.

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@DSmith Welcome to the Brotherhood

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@DSmith

Welcome to the brotherhood. David and ‘great job’ on your ‘gunsmithing!’ :+1:

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Well, I followed a video… :grinning:. I did practically all the internal upgrades (not the extended mag release, the original of which I had filed down and polished). Here’s hoping I’ll never have to pop mine open again. Up next: sight mount.

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@DSmith welcome to the forum david and merry christmas and a happy new year

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Just an update. At the range yesterday I used CCI Blazer 124gr and didn’t have a single misfire in 150 rounds. Didn’t do anything to the Sub2k at all. I guess this rifle is gonna be picky with the lighter hammer spring but I can live with it. I bought the Winchester white box at Wally World a couple months ago because it was only 18 cents a round. My gun store has the CCI for the same price. Rural King has Federal 115gr for 16 cents a round.

Here’s how it’s doing at 25 yards (I need to readjust the sights a little).

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