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Discussion Starter · #1 ·
Anyone else have this problem? Not sure what the deal is... the bolt just gets stuck forward and won't budge no matter how much force I dare apply. Everytime I'd have to field strip the gun... once I get to the bolt removal part, I have to jiggle the bolt around quite a bit just to finally get it to release backwards.
 

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Discussion Starter · #3 ·
That's exactly what it seems to be. I have it covered with CLP now, but it's still getting stuck. However... now I can keep jiggling the bolt handle back repeatedly with force until it frees itself and lets me cycle the bolt. I think I've never noticed this during regular firing because it has enough force to disengage the bolt each time, but damn... did I just reassemble it wrong? I don't see how since it seems so fool proof lol. Maybe something with the firing pin and that retaining pin?!
 

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Discussion Starter · #5 ·
I will try snap caps, but I don't see how that would make the problem disappear. It seems like with live ammo, there's enough force generated to disengage the bolt lugs. (Maybe this is even causing damage?)

But with regular force/manipulation, it's darn near impossible to get the bolt to disengage. Just manipulating the bolt and the cam pin itself, it seems like it's catching a little. I'm really hoping it's me being stupid and reassembling the gun improperly instead of a manufacturing defect. Maybe I'm screwing up a step with the bolt, cam pin, and firing pin?

Problem looks sorta like
 

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Maybe something with the firing pin and that retaining pin?!
I don't know if this would cause the problem but do you have the retaining pin in properly? Its not supposed to sit flush but the o-ring needs to seat into the carrier. The first time I disassembled my carrier, I was worried about pushing too hard and I wasn't seating the retaining pin properly.
 

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Discussion Starter · #8 ·
I'm pretty sure I have my retaining pin in properly like you described.



Here's an update... got my snap caps in.
I can manipulate the bolt all day long with no problems with nothing chambered as long as I don't pull the trigger. Once I pull the trigger... the bolt gets locked forward and I can't retract the bolt easily if at all without taking apart the gun.
Using a snap cap... I pull the trigger... and with tremendous difficulty (Like buttstock into the ground and me shoving down the charging handle, I can get it to eject the snap cap and chamber the next one)

This... isn't normal, is it? I'm thinking it has to do with something revolving around the firing pin causing the lugs to not rotate back out!
 

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I'm pretty sure I have my retaining pin in properly like you described.



Here's an update... got my snap caps in.
I can manipulate the bolt all day long with no problems with nothing chambered as long as I don't pull the trigger. Once I pull the trigger... the bolt gets locked forward and I can't retract the bolt easily if at all without taking apart the gun.
Using a snap cap... I pull the trigger... and with tremendous difficulty (Like buttstock into the ground and me shoving down the charging handle, I can get it to eject the snap cap and chamber the next one)

This... isn't normal, is it? I'm thinking it has to do with something revolving around the firing pin causing the lugs to not rotate back out!
Depends on how many times you dry fired it prior to purchasing the snap caps.
 

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Discussion Starter · #10 · (Edited)
Are you saying I may have damaged the firing pin? Because I can't seem to find any damage to it.

Just wanna get this figured out so I can get it repaired before it worsens. When I first bought the Scar 17, everyone said it was gonna be perfectly fine to dry fire it.
 

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Bolt, bolt cam pin, and firing pin are not designed to be repeatedly dry fired on empty chambers.

How many times have you dry fired the weapon?

Did the bolt lock-up condition exist with he first time you dry fired it or has it manifested after a number of dry firings?

Did you purchase the weapon new?

Have you inspected the bolt cam pin?

Have you inspected the entire bolt body, as well as the locking lugs?

Have you inspected the barrel extension to visually ensure it is void of anything that may be lodged?

Have you inspected the extractor, extractor cam pin, and retaining ring?

Is the weapon lubricated?

Tough to diagnose an issue while blind-folded but one thing is certain, repeated dry-firing should be avoided. Not sure who "everybody" is that suggested it was acceptable to dry-fire weapons in general, but suggest you stop listening to their advice.
 

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I have been around for a while (56 years old now - immersed in guns since 12 years old) - Still, I do not have all the experience that some do here. When asked who is Everybody that says it is not a problem (dry firing), I would say the OP's experience is the same as mine and I do not know the OP. The Vast majority of wisdom I received said don't worry about it on a modern gun.
I have fired tens of thousands dry rounds on M1a and M1 rifles preparing for service rifle competitions and never had a problem - though I do know some guys had firing pin problems, they did not seem to fail while dry firing. I know the SCAR is not the same a an M1a/M1.
Again, I took the advice of lots of people around me who said dry firing is not a problem - apparently it can be.
It will be interesting to see what the final diagnosis is on this problem...
 

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Discussion Starter · #17 · (Edited)
Thanks for all the posts so far guys. I just got back home and made a quick video hopefully showing y'all what you need to see.

Apologies for the shaky fingers, been up for 2 days studying. :frown:

Rifle has been lubricated and it's still getting caught up. I purchased it new around a year ago. Have around 300 rounds or less through the rifle with 0 malfunctions on the range. Easily dry fired less than 50 times total... maybe half that? Still have issues now with snap caps. I honestly can't recall if it ever had this problem when I first received it... it's been a year or so now. Left the rifle in my parent's gun safe and only just recently returned home to retrieve it.


Basically my theory is I'm somehow messing up the firing pin's position on assembly. Not sure how though...
Pretty sure it isn't just a bolt thing since there are no hang ups unless I pull the trigger leading me to believe it's the firing pin/channel.


Here are some pictures of stuff I realized I left out in the video or weren't super clear.







Feel free to be brutally honest if it's me being an idiot. I think I've followed the proper assembly/disassembly steps so I'm really at a loss on the cause of the problem.
 

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The back of the firing pin protruding when the bolt is all the way back is normal. If it was flush with the receiver, how would the hammer contact it to set off the round?

The cam pin looks pretty chewed up in the first picture, that could cause the bolt to hang up a little when you move it back and forth (like you showed in your video). I doubt that would keep the bolt from unlocking though. It's probably a side effect of whatever is causing your problem.

Sounds like with the pressure from the hammer on the firing pin is enough to lock everything up. As the other forum members suggested, it could be an out of spec firing pin (bent or peened). Is the firing pin channel clean?
 

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Check the firing pin for being bent, by removing it and rolling it on a flat surface. Because of the pin shape, you will have to let the contoured end of the pin to hang over the edge of your flat surface and roll it back and fourth watching for, on the flat surface side, it to have a bow in it and on the end overhanging to have a oscillation to it. I suspect a bent firing pin because of it not being centered in your bolt.
 

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I think several people have pointed to the most obvious solution that the tip of the firing pin is getting stuck in the hole of the bolt face.

Remove the pin and the bolt, and push the pin into the back of the unassembled bolt, and see if you can get the tip of the firing pin to extend out the face of the bolt. I'm sure there is a published number for how far it is supposed to protrude, and I'm guessing it is about 0.050. You can measure it with a calipers. The assumption is that the very tip of the pin is either bent, or too fat to fit comfortably in the hole, so when you pound it it with the hammer, it does not want to pull back out.

Get a sharpie, color in the tip of the firing pin, put it in the back of the bolt to verify it is poking all the way through, then take it out and see where the sharpie ink is rubbed off. You could try it by dry firing as well.

THe less obvious thought I have is if the real problem is the BCG hanging up on the hammer face. I can't think of how that would happen, but it would explain how you could get the bolt out by disassembling the rifle. If the firing pin were really wedged into the bolt such that you could not cycle it, you could also not disassemble it. So I'd say that when it jams, try just removing the lower. Cock the hammer by hand, re-insert the lower, and see if that fixes it.
 
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