Palmetto PA-10 failure to eject

[W.E.G.]

I removed the Palmetto barrel from the receiver yesterday. 

The barrel nut seemed appropriately-tight as I removed it. I had to piggyback a big-ass trailer-hitch box-end wench over the handle of a 12” adjustable wrench to break the nut loose. No threadlocker was present on the barrel nut. Some sort of white-colored grease was evident on the threads. 

Once the nut was removed it took some legitimate wrestling to get the barrel to pull free of the receiver. That’s a good thing.

I couldn’t see any flaws on the mating surfaces of the barrel extension or the receiver. 

I cleaned up the shoddy grinder-marks on the feed ramps before re-installing the barrel. After applying some fresh synthetic grease on the threads, I used the same piggyback wrench trick to tighten the barrel nut. I snugged-loosened the nut three times before sending it to full torque. 

Range trip today to see whether it’s still shooting vertically-strung groups.

[W.E.G.]

This is acceptable.

200 yards. Prone. Sling supported. Fired from magazine.

41.5 IMR4895 - 168 SMK

[Sisco]

Glad you got it straightened out.

[Albroswift]

woohoo!

[W.E.G.]

So, here's what it took:

• replaced short Palmetto gas tube with rifle-length AR10 gas tube
• replaced non-functional Palmetto extractor with Fulton Armory AR10 extractor and extractor-spring
• replaced basic trigger with Geissele National Match trigger
• replaced basic collapsible buttstock with Magpul UBR generation-1 buttstock
• installed Magpul 0.70" thick enhanced buttpad
• replaced basic carbine buffer with KAK 5.3 ounce carbine buffer
• replaced Palmetto carbine buffer spring with DPMS LR-308 buffer spring (not sure there's any real difference between the two)
• experimented with adjustable gas block, but ended up just using the Palmetto gas block (its decent IMO)
• polished ham-handed grinder-marks off feed-ramps on barrel extension
• added as many keymod cheese-grater bits as the handguard would accept (main purpose was to increase weight)
• added Magpul XTM forearm panels to rearmost cheese-grater bits to keep cheese-grater from eating my left hand during sling-supported firing
• mounted pushbutton 1.25" sling swivel to forward cheese-grater bit at 6 o'clock to comply with NRA rule for service rifle swivel location
• mounted Turner all-weather service-rifle sling
• added Stealth Ballistics buttstock weight to UBR stock (improve balance and increase weight)
• obtained wrench for removal of barrel nut from Harbor Freight (12" adjustable wrench) - modified wrench by thinning wrench-jaws and wrench-frame with angle-grinder and chainsaw file.
• removed barrel for inspection, then reinstalled re-torqued the barrel nut with a couple extra ugga-duggas (technical term)

Now I just need to go shoot a 500 in the National Trophy Individual Match. LOL!

[W.E.G.]

Almost forgot to mention, Larue LT-104 scope mount and Leupold Mark AR green firedot 1-4X scope!

 

[W.E.G.]

Pic taken before installing the Magpul XTM cheese-grater covers

 

[98Z5V]

Good work on that, man - I think you're the first person I've seen use the Armalite AR-10 extractor as a replacement for a faulty stock extractor, so kudos to you on that one - good job. 

[W.E.G.]

I replaced the extractor and spring assembly in the Palmetto bolt. Some folks reported significant issues with primer-extrusion with the Palmetto bolt. I have not experienced this with my handloads or Spanish “Santa Barbara” surplus 7.62.

 

These are the Fulton Armory parts I installed in the Palmetto bolt:

 

 

[W.E.G.]

I plan to shoot the rifle in an 800 point match next weekend if I don’t get stuck calling the firing line. If I get stuck with that job, I may stay late and shoot a simulated match if the heat index is bearable.

[unforgiven]

Outstanding job brother 👍

[98Z5V]

8 hours ago, W.E.G. said:

I replaced the extractor and spring assembly in the Palmetto bolt. Some folks reported significant issues with primer-extrusion with the Palmetto bolt. I have not experienced this with my handloads or Spanish “Santa Barbara” surplus 7.62.

 

These are the Fulton Armory parts I installed in the Palmetto bolt:

 

 

The Fulton Armory parts are DPMS-based, not AR-10 based. I completely missed the "Fulton Armory"  before the "AR-10 extractor" part of that.

This has me thinking though - I'm going to try an Armalite AR-10 Extractor in a Toolcraft DPMS-based bolt.

[W.E.G.]

Another range trip today.

Heat index 101*

Sorry for the blurry pics. Didn't have my glasses on when I took the pics of the targets. Couldn't tell that the camera wasn't focusing.

The wandering-elevation issue appears to be resolved.

I was pretty gassed by the time I tried to shoot the sitting position. I was playing around with some different ammo and also turning scope-turret knobs. Doesn't explain the scattershot. No, the scattershot was me trying to shoot a .30 caliber service rifle rapid-fire from sitting position when I was gassed from the heat. Of course, the camera decided to focus when I was looking my worst. Keeping it real.

[washguy]

Damn WEG.....you almost got it to where it stays on the paper    Wash

[unforgiven]

Good shooting brother 

[W.E.G.]

While cleaning the PA-10 today, I noticed that the head of the firing pin is beginning to "mushroom."

This pic shows the condition of the firing pin after approximately 300 rounds.

No evidence of deformation at the tip of the pin (the part that strikes the primer).

I am running a Geissele "National Match" trigger group with this firing pin.

Since taking this pic, I have used a file to remove the deformed metal from the head of the firing pin.

Edited July 21, 2019 by W.E.G.

[98Z5V]

Very interesting observation, and very good catch.   Interested to see if it keeps deforming.  Even on super-high round-count issue M4s, with shot out barrels, I haven't see the firing pins mushroom like that.

[W.E.G.]

It bears comparison that the AR-15 type firing pin has a much more rounded/tapered head. 

I’ve wondered why the Palmetto and DPMS pin-heads have such a flat-angle head-shape.

[98Z5V]

8 minutes ago, W.E.G. said:

It bears comparison that the AR-15 type firing pin has a much more rounded/tapered head. 

I’ve wondered why the Palmetto and DPMS pin-heads have such a flat-angle head-shape.

Armalite AR-10 firing pins have the same profile, man.  Just a little different in dimensions because of the firing pin spring.

[survivalshop]

I would replace it with another known, reputable Manufacturer . 300 rds? Its too soft , shouldn't be doing that even at 3K rds. 

[98Z5V]

1 hour ago, survivalshop said:

I would replace it with another known, reputable Manufacturer . 300 rds? Its too soft , shouldn't be doing that even at 3K rds. 

^^^   I concur completely, all the way. 

[W.E.G.]

I haven't kept close-count on the number of rounds fired.

Here is what the Palmetto bolt looks like after around 300-400 rounds. 
Probably closer to 300.

Lots of peening of the bolt lugs.
Raising enough burrs on lugs to snag cotton-fibers from Q-Tips.

[jtallen83]

I don't think I would fire the weapon with that bolt.............

[98Z5V]

9 hours ago, jtallen83 said:

I don't think I would fire the weapon with that bolt.............

Yep, that is nowhere close to "normal wear" in the least stretch of the words.  I'd be taking advantage of their "lifetime warranty" and getting a new bolt.

Well, actually, I wouldn't.  I'd shiit-can that thing and buy a ToolCraft bolt.  Whole BCG, for that matter.  I'd get that outta my gun.

[98Z5V]

9 hours ago, W.E.G. said:

 

Look at that square-faced ejector...    This thing mis-feed alot?  The square shoulder on that ejector needs to be rounded - or it's gonna be hell with every round that feeds from the right side of the magazine.