550/650 Strong Mount Flex?

[CB45]

As title says. Last night I ran my first batch of ammo through my new 650 mounted on a 550/650 SM.

The SM flex's on the down stroke. All bolts are tight. Its purely flexing on the legs of the SM and where the bends are for the press bolts.

Two problems I'm experiencing;

1. The case feeder moves about 1.5.inches due to the flexing

2. Inconsistent C.O.A.L

I can't come up with any other reasons for the inconsistent c.o.a.l. so I'm blaming the flex at this point.

Is the flex normal? Would a 650 Only SM have less flex?

All my attempts to search to search for this issue just resulted in praise for the SM. Has anybody seen this before?

[james5m]

Yes..Noticed the flexing on a freinds 650. but does not have a issue with OAL since he clamped the tool head down. With the case feeder moving around we seem to get alot of case jam ups at the casefeed funnel, but the extra shaking it also affects the RCBS bullet feeder sorting plate knocking the bullets out of the slot. We are working on a way to cross brace the strong mount to eliminate the flexing. When we figure it out, I'll let everyone know

[CB45]

Hmmm... Thanks for the response.

Seems not many people are willing to speak ill of the SM.

I'm going to call Dillon after lunch.

[Sarge]

Don't know if my case feeder was moving that much but it was shaking enough to flip cases once in awhile. Seems like a lot of us have ended up mounting the case feeder directly to the bench to keep it from shaking.

There is bound to be some movement but it sounds like yours is really flexing a lot. I went with the 650 SM and like it a lot. I can't really speak ill of something that lets me work out spent primer mods and have much larger bins to catch loaded ammo.

[RangerTrace]

Mine moves VERY little and does not cause any issues with the loaded ammo.

[Charles Appel]

I'm using a 550 and a 650 - both on 550/650 Strong Mounts. My Strong Mounts are bolted to hardwood boards and to the presses. The boards are then clamped to the bench. I haven't noticed any flex in the mounts on either machine.

1.5 inches of motion seems radically out of line to me. Have you talked to Dillon about the problem.

[uod]

I use a 550 with a SM ... and I've loaded on a 650 with a SM. I've never noticed any sort of flex. I can imagine a 1.5" flex would start to get really annoying after a while.

[98sr20ve]

I can't see why the mount would be creating the flex. If you have one that has a bend that does not interface with the base of the press then it could flex I am sure. BUT the flex on my bench is always a result of the bench not the press/sm. Every bench has some small amount of flex. And that gets multiplied by the length of the casefeeder arm. So it shows up the most at the casefeeder. If you bench is not 2 inch's thick it will flex more then it should. I did this to settle it down, it made a huge difference. Mine was not moving near as much as yours.

[Mastiff]

98sr, I like your solution. I don't experience the flex. But I'd like to see what that Strong Mount base is screwed down on, meaning the bench top. If that bench top or whole bench for that matter isn't rock solid, anything can throw you off your game...

Dog

Edited December 6, 2013 by Mastiff

[CB45]

Here is the flex. Pressure applied is typical for resizing 9mm. I actuated the handle with my weak hand to show that I wasn't horsing the arm, forcing the flex.

This is what it looked like when I loaded 100 RDS last night.

https://www.youtube.com/watch?v=uQeX7h-SBbw&feature=youtube_gdata_player

Edited December 6, 2013 by CB45

[98sr20ve]

How thick is your bench?

[RangerTrace]

WOW, that doesn't look right at all to me!!

[98sr20ve]

I think it's bench related. The Strong Mount will transmit front to back forces really well into the bench because of the length of the legs. But sideways force is going to have more ability to flex the top of the table then people might initially think. The bench needs to be thick enough to counteract this process.

[TrukSnave]

yeah thats definitely messed up!!!

[CB45]

Bench doesn't move during this lateral flex. Bench top is constructed with 2x4's.

If the bench moved, you would see the camera move.

I think I'm going to take it to a local reloading shop tomorrow and see what they have to say.

Thanks for everyone's time.

[Sarge]

WOW, that doesn't look right at all to me!!

Same here. looks like maybe it's mounted with the legs too close together or something?

[RightYouAreKen]

Wow. Can't say I've ever seen my 650 strong mount flex like that. I get a little, let's call it a "jiggle", at the case feeder, but it's never cause me any problems. I wonder if when the strong mount was bolted down if the legs weren't quite in their natural position and square to both the bench face and the 650 mount face?

[John Wayne]

I watched the vid twice, shocks me. I have the 550, 650,sm's no flex. I do have the correct size bolts (quarter inch I think) with flatwashers on top of the presses with large fender washers next to the wood and then normal washers with nylon locknuts. All torqued really tight and crushing into the wood. I doubt Dillon has used thinner metal but...?

[RDA]

Either the bolts aren't tight or the bench is flexing.

[Mastiff]

Wow. Can't say I've ever seen my 650 strong mount flex like that. I get a little, let's call it a "jiggle", at the case feeder, but it's never cause me any problems. I wonder if when the strong mount was bolted down if the legs weren't quite in their natural position and square to both the bench face and the 650 mount face?

This is the correct answer. The mount has to seat naturally on the bench all 8 holes 4 on the bench and the 4 on the base of the machine casting) must line up dead nuts. I realize there is some play, but less or none is best.

Dog

[98sr20ve]

Bench doesn't move during this lateral flex. Bench top is constructed with 2x4's.

What is tying all the 2x4s together.

[natgas]

It has to be that the SM was not sitting completely flat when it was bolted down.

[CB45]

I remounted. Same issue. SM was resting naturally when I mounted it. Mount is not bound up or attateched funny.

About 100 2.5" screws hold my bench together. The bench absolutely is not the problem.

Guess you guys didnt read it before, THE METAL IS FLEXING!

I think a 650 Only mount would flex less, as its 2" shorter.

Taking it to where I bought it last Friday. Maybe they'll have an idea to firm up the SM.

[Mastiff]

I remounted. Same issue. SM was resting naturally when I mounted it. Mount is not bound up or attateched funny.

About 100 2.5" screws hold my bench together. The bench absolutely is not the problem.

Guess you guys didnt read it before, THE METAL IS FLEXING!

I think a 650 Only mount would flex less, as its 2" shorter.

Taking it to where I bought it last Friday. Maybe they'll have an idea to firm up the SM.

Email Dillon the video. They'll know what's going on. I just can't imagine what would create that side load. Edited December 7, 2013 by Mastiff

[NoSteel]

Looks to me that it is force related at the seating height (top of stroke). Do you see same flex when seating primer? I'm guessing not. There should be similar force applied then causing the mount to flex then also if mount / bench problem.

Do you have a die making contact with shell plate before you reach the bottom of the stroke?? If so continuing to apply pressure does cause this an will without a doubt cause OAL issues since different degrees of pressure will cause the shell plate to be depressed. Back the dies of slightly to test and see if problem lessens.. Just a thought....