[silence]
This is a review of a thrust bearing for the Dillon 550B shellplate.
The purpose of a thrust bearing, is to make indexing smoother by placing ..
roller bearings ..
between the index sprocket .. and the shellplate bolt.
This will give a smoother action as compared to having the bolt directly against the index sprocket.
The thrust bearing I am reviewing, was made by Slash K Guns of Tucson, which I purchased from UniqueTek.
Their internet URLs are in the video description.
The brand name of the thrust bearing is Turbo Bearing.
The turbo bearing comes with an index sprocket, whose opening
has been widened to accommodate the thrust bearing.
Comparing the index pocket .. to the standard Dillon index sprocket.
You can see how much wider it's been made.
And it comes with .. the roller bearing.
Let's take a close look at a roller bearing.
[silence]
And it comes with two washers .. and instructions.
Installation is simple. We just need to remove the current index sprocket.
You do that by raising the shellplate.
And using a 1/8 hex key, remove the lock screw.
[silence]
Lower the shellplate.
And remove the bolt.
I find bolt removal easier, if I hold down the shellplate.
[silence]
Then remove .. the index sprocket.
And replace it with the one that came with the thrust bearing.
[silence]
Then we insert one washer.
Roller bearings. And it doesn't matter which side is up because ..
each side will have a washer against it.
[silence]
And reinsert the bolt.
[silence]
Again, I hold it down.
[silence]
Take it down until it has contact.
What I do, I just slowly back it off.
Until .. I make sure I get rid of all vertical movement. I actually have some, so a little bit tighter.
Actually, I find it helpful if I just .. push the arm down to keep ..
[silence]
Alright, the movement is gone there.
At this point, I will reinsert the lock screw.
[silence]
And check it.
[silence]
The installation is complete.
And while you cannot see it. I do feel a much smoother operation.
After loading about a hundred rounds, I started to get inconsistent bullet seating.
When I investigated, I saw that the shellplate had become loose.
So I removed the lock screw. Re-tightened the bolt. And reinstalled the lock screw. Making sure it was tight.
But the problem returned after about a hundred rounds.
It took me a while to figure it out.
But the issue, is that the thrust bearing and washers ..
raised the bolt, a little less than the thickness of two nickels.
Let's compare it.
Here's an index sprocket with the thrust bearing.
And here's one without.
Let's compare that again. With a thrust bearing. And without.
Because the bolt is raised .. it is sitting higher in the ram.
And when I looked into the opening, where the lock screw goes.
I saw that the bolt, had been raised just enough.
So the lock screw, was not able to make contact with the bolt body.
Instead, it was trying to contact the threads.
Let's take a close look at the bolt placement, with and without the thrust bearing.
As you can see in the image on the right.
There is not sufficient enough surface
for the lock screw to hold the bolt in.
And this is what was causing the bolt to come loose.
So I had to remove and not use the thrust bearing.
Before buying, I suggest you remove the lock screw.
Unscrew the shellplate bolt a little less than the thickness of two nickels.
Something like. Where the head of the bolt just sits right above the index sprocket.
And look in the lock screw opening, and see if you can see the bolt.
If you see the bolts body, then you are a candidate for the thrust bearing.
Else, if you see threads, then I would not recommend the thrust bearing.
Since my experience, has been the lock screw is not capable of securing the bolt
if it only contacts the threads.
I also tried using the roller bearing.
Without the washers.
[silence]
Like this.
And while it did provide a smoother action, it still raised the bolt too high.
And I also tried.
[silence]
Using a single washer.
[silence]
While it did allow the lock screw to contact the bolt body.
It only had a small improvement for indexing.
If like me, you're not able to use the thrust bearing.
There are some things you can do to make indexing smoother.
First .. make sure that both sides of the shellplate, do not have any accumulated dirt or grime.
Also ..
[silence]
Clean the index sprocket opening.
And ... the bottom of the shellplate bolt head.
Second. Check the under surface of the bolt head.
By just turning it against your thumb.
And see if there's any rough spots.
If so. Just use a metal file to smooth them out.
Third. Try putting a little gun grease on the bottom of the bolt head.
It's important to use gun grease and not oil.
Grease stays where you apply it. Oil does not.
Finally. Make sure that the bolt is not too tight on the shellplate.
I always manually tighten the bolt without using a hex key.
You want the bolt just tight enough to keep the shellplate from having any vertical movement.
Any further tightening, only makes it harder to turn the shellplate.
I hope this video was useful to you. And thank you for watching.