Rimx with ModX conversion likes Vudoo mags better than RimX Mags

DrA1

Private
Minuteman
Aug 30, 2024
33
36
Louisiana
The title says it all.

I just picked up a Rachel Precision Brux on a RimX action with the ModX bolt.
The guns shoot beautifully- tight groups at both 50 and 100 yards.

But here is the issue — I have 2 RimX mags with extensions and they are well built, but no matter how I adjust them, they do not feed consistently, so I decided to try a polymer Vudoo mag, as I had some with me and BINGO—- flawless feeding—— has anyone else experienced this.

When watching the rounds feed, it appears that the round hits the chamber a little low and shaves some lead and the cartridge hangs on the lower (6 o clock) aspect of the chamber. Probably about 1 in every 20 rounds does it. SO…… I adjusted the mag to sit as high as possible however that did not fix the problem— I believe the issue is the angle on the front edge of the rimx mag.

The Vudoo mag on the other hand feeds flawlessly over hundreds of rounds.

Thoughts??
 
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Try taking the extensions off, assuming you have the original floor plates. I only experience feeding problems with my RimX with the Zermatt 5-round extension in place on one magazine, and it can happen anywhere in the cartridge stack. The round pops off the stack in front of the extractor and gets shoved into the chamber, requiring steel fingernails or a tool to pull it out.
 
Try taking the extensions off, assuming you have the original floor plates. I only experience feeding problems with my RimX with the Zermatt 5-round extension in place on one magazine, and it can happen anywhere in the cartridge stack. The round pops off the stack in front of the extractor and gets shoved into the chamber, requiring steel fingernails or a tool to pull it out.
Do you have the modX conversion or the factory original bolt face?
does the chassis have an adjustable magwell such that chassis adjustments would raise the mag?
it does not.
 
It's the original bolt face... although my point stands. I suspect that the original spring isn't quite strong enough for the height/weight of the additional cartridges.
I wasn’t implying that the bolt face was my issue, just wasn’t sure how many of the ModX rifles have made it into the wild.

I believe you are correct, based on speaking with several other shooters that have had similar issues with extension and feeding difficulties.

I’m going to remove the extension and shoot it today (but I also ordered the tandemkross green springs as the hopeful solution with the extension)

Thank you for the help
 
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I wasn’t implying that the bolt face was my issue, just wasn’t sure how many of the ModX rifles have made it into the wild.

I believe you are correct, based on speaking with several other shooters that have had similar issues with extension and feeding difficulties.

I’m going to remove the extension and shoot it today (but I also ordered the tandemkross green springs as the hopeful solution with the extension)

Thank you for the help
Please post back with your results - I'm interested for sure.

My feed failures with the extended magazine are frequent enough that I wouldn't even think about running the rifle in a match with "normal" par times. I did use it in a little monthly match series in 2023 which had long par times... and I usually had one or two failures every match, always with the extended magazine.
 
Please post back with your results - I'm interested for sure.

My feed failures with the extended magazine are frequent enough that I wouldn't even think about running the rifle in a match with "normal" par times. I did use it in a little monthly match series in 2023 which had long par times... and I usually had one or two failures every match, always with the extended magazine.
I wouldn’t consider using those mags in match, but hopefully will get it sorted out.

At least I have other mags that do run well.

I’ll let you know the results.
 
I run a ModX in an ACC Elite with a RimX mag fitted with the +4 extension from Zermatt, and see no shaving.

My only reliability issue is the bolt moves so freely that shoving it firmly into a bag on a solid prop can send a round halfway forward, and if I back the bolt up from there I get a jam. Would love to have a detent bolt retention mod done to it, probably have a smith look into that for me sometime this year.