View Full Version : BHO ?

January 18, 2009, 22:55
I gotta STG kit on DSA #2 and had some pro help putting together and rifle is awesome.........except the bolt hold open isn't working properly. By this I mean that mt mag pushes it up some but not enough to engage on last shot. It's got the typical little tapered pin but I don't think that's the problem. It seems that the bho itself is dragging in the DSA receiver. Anyone have this problem and fix for? I was thinking of filing or emory cloth on bho but thought I'd ask first. And, uh, thanks righteous FAL knowledeable dudes for addressing bho's at least one more time. I found lots of topics on search but most seemed to revolve around which foot, which rifle had which, which rifle didn't have, or the PITA pin gouging followers but not too much on dragging.

Thanks again...

January 18, 2009, 23:03
And I thought this was about the president elect.

January 18, 2009, 23:52
wait 6 months and I'll post again about how my BHO ain't working and then it'll be about the Prez...:wink:

January 19, 2009, 08:07
Here's how I'd troubleshoot the dragging.

Check the cross pin (pivot) is correctly lined up with the BHO spring. A lot of them are not below the spring fully, causing drag.

Check the spring itself is crud free, as that will drag as well if there is "stuff" inside the hollow tube.

Smooth, or polish but don't grind down the shaft of the BHO. (Scotchbrite with oil does a great job here)

Finally polish the inside of the bho tunnel in the reciever. This is a little hard to get at but I've used a small bore brush chucked in a cordless drill.:uhoh:

Go step by step till you get proper function then stop. There is no need to go overboard by polishing everything.

L Haney
January 19, 2009, 09:40
95% of the time what brownknees just said will get you going. I like to use a pointed slave pin during assembly to make sure the pivot pin goes through the bho spring assembly in the right place. I had an additional problem during initial setup. The pin that engaged the follower was about a millimeter too short, and would sometimes bind the follower and lock the magazine in. I drove it out and replaced it with a longer pin that I sized and shaped to function every time. With the dust cover removed, it's real easy to see what it's doing, and figure out what needs attention.


January 19, 2009, 11:03
Good catch, I forgot to mention that little detail:rofl:

If you use a slave pin ( & I would) just make sure you don't just duplicate a binding spring when replacing the pivot.Don't ask me how I know this little tidbit!

January 19, 2009, 11:05
Check the bolt hold open itself for smooth function.
The spring in them is very weak and it doesn't take much crud to bind it up and make it work poorly, or not at all.

Load it up with penetrating oil or even WD-40, turn it upside down and start working that spring up and down.
A nail will work for depressing the spring.
Let it SNAP. Keep spraying it and working it.
It's messy, but usually doesn't take too long.