I recently noticed when practicing bolt override malfunction clearence drills that when I was following Mike Pannone’s method of pushing up on the bolt catch so it catches the bottom front of the bolt carrier that the carrier would slip off. Sometimes it would even slip off before “karate” chopping the charging handle back. I initially did this on my factory Noveske (~3.5 yrs old) build with a standard lower. I then tried it with my work S&W M&P 15 and the bolt catch would easily hold onto the bottom of the bolt carrier. Even when i tapped the flash hider lightly on the carpet without holding the bolt catch down it still held.
First I put the Noveske BCG in the S&W complete rifle and it held just fine. S&W BCG in Noveske complete rifle did not hold. S&W lower on Noveske upper with either BCG held. Noveske lower with S&W upper neither BCG held.
I also tried a Noveske Gen 2 lower with a colt defense bolt catch that i installed and it also did not hold (not enough engagement)
Basically what I finally figured out what was happening was the bolt catch engagement on the Noveske lower was only catching the beveled cut on the underside of the bolt carrier. The S&W bolt catch had just enough more engagement that put the bolt catch above the beveled cut onto the flat surface just below the bolt.
My hope is that i just can replace with a new bolt catch and it isn’t the lower that is slightly out of spec…
Anybody else experience this that can offer me some guidance/remedy?
It should be engaging the bolt face not the carrier face. If it engages only the carrier face, you wouldn’t pick up a cartridge upon releasing the BCG. Put an empty mag in and pull the charging handle while wathcing the carrier let it engage just the Carrier lip as you are describing above and look at the position of the bolt face. It would be sitting on top of a round if you inserted a new mag. Now pull the charging handle further back and let it engage the BOLT face and look at how it will be able to pick up a round when you inserted a loaded mag.
I’m just talking about when doing bolt override malfunctions…they both work normally. When clearing a bolt override malfunction you normally can’t pull the BCG all the way to the rear hence the reason for having it hold on the bolt carrier. tracking?
I’m not familiar with this technique, but I’d have to agree with steyrman13 in that yeah… you can usually make a bolt catch grab the carrier, but it’s not supposed to do that.
Gotcha. I guess I am not familiar with that way of simulating that malfunction.
I would definitely start with replacing just the catch to confirm if it is in spec or not. it is much cheaper than a complete lower. Mine engage and look to be touching the bolt itself when replicating what you are describing above. Hopefully it is just an out of spec bolt catch.
Sorry that I’m not being clear…I know its NOT supposed to do this it is just a helpful thing when clearing a bolt override malfunction quickly (since its a lot more difficult to pull back the BCG far enough to use the bolt catch to engage the bolt. I just never looked at the differences in bolt catches and wasn’t expecting it…but I suppose I should know better.