Index lever shoulder bolt coming loose?

[WSA]

I've got a RL1100 with a Mark 7 autodrive on it. The unit worked great for quite awhile- about 50K rounds. Then the index lever bolt kept working loose. If I tighten the bolt very hard, it's too tight to allow the return spring to operate. When I tighten it just good and snug- which is how I had it originally- it works itself loose. Shellplate will index great for the first dozen revolutions then start getting erratic and finally doesn't index enough and everything stops as the index pin hits the shellplate. 

 

I've tried a lock washer but that didn't have any effect. 

 

Any ideas on what to do? Locktite? 

 

Thank you for your help

[Johnnymazz]

Did you try replacing the bolt, they bend with automation

 

[WSA]

I did not know they bent. Doesn't look bent but that doesn't mean there isn't a small variance. Which I suppose could make things wobbly and unscrew the bolt. 

 

I'm guessing the only source for these bolts is Dillon? Not the end of the world but I'm in Canada so shipping from the USA seems to take forever these days. 

[George16]

Check your local hardware store. You can also order them from McMaster.com. I think it’s a 1/4”-20 shoulder bolt iirc.

[AHI]

10 hours ago, WSA said:

Any ideas on what to do? Locktite? 

Per the directions 242 Loctite.  Clean with brake clean, dry .Then apply. Let it set 24 hours to cure.

[Johnnymazz]

Place the ram at the full upstroke, if there is any slop in the index arm, the bolt is bent

[Johnnymazz]

3/8-5/16-18X1. 1/2 inch UNC

[ddc]

As others have pointed out that shoulder bolt can get bent and definitely cause indexing problems.

It may look straight but it could still be bent. It doesn't take much.

 

I've never had a problem with getting that bolt so tight the spring is compressed to tightly. That doesn't sound right.

 

I wonder if it might be related to the following:

 

I had a problem with the the pivot pin into which that bolt is threaded. The threads were too loose. Caused a lot of trouble with indexing similar to having a bent shoulder bolt; eventually had to send it back to Dillon for them to figure out what the problem was.

 

Now that I'm aware I can replace it myself if it happens again but at the time neither Dillon nor I had a clue.

[WSA]

3 hours ago, Johnnymazz said:

3/8-5/16-18X1. 1/2 inch UNC

 

 

Thanks everyone, this has been a big help. I took off the index roller bolt as well and looked at it and sure enough it is bent. Also the roller bolt spring looks mangled so I'll try to find a suitable replacement.

 

So that's probably causing some inconsistent wobbling on the index lever too. I think I'm just going to order a few of each bolt. 

 

I assume 3/8-5/16-18X1. 1/2 inch UNC is the designation for the lever bolt, do you also happen to know the same information for the roller bolt?

 

 

Edited April 28, 2022 by WSA

[ddc]

From McMaster-Carr:

For the index roller shoulder bolt:

91259A628 Alloy Steel Shoulder Screw, 3/8" Shoulder Diameter, 1-1/2" Shoulder Length, 5/16"-18 Thread

For the index lever shoulder bolt:

91259A619 Alloy Steel Shoulder Screw, 3/8" Shoulder Diameter, 1/2" Shoulder Length, 5/16"-18 Thread

[WSA]

Thank you for your help!

[WSA]

I should mention that I replaced the roller bolt and all seems good now. Great information folks!