I was wondering if anyone has experience with the ESS Chassis for a Winchester Model 70 had attempted to put one on a FN SPR? I emailed MDT to see if it was compatible and they answered back as they're not really sure... They think there might be a trigger issue but can be easily modified on the chassis system itself, they just don't have a FN SPR sitting around to test it.
MDT ESS M70 Chassis Compatibility on FN SPR?
- Thread starter Docmedic
- Start date
Im pretty interested in this too. I didn’t realize mdt had an inlet for the model 70. I also have an fn spr that’s destined for a chassis. If no one knows for sure in a couple of days I’ll pull my model 70 with moa trigger out of the stock and measure the trigger. I’ll try to do the same with my spr. Not sure when I’ll have a chance though.
I didnt have a chance to pull my actions and measure the triggers last night, and turns out I don’t think it will be necessary. I had a “light bulb” moment driving to work this am. The Winchester actions (including FN SPR) need to be modified to run an AICS magazine. My thought is that since the action already needs to be modified by a gun smith to work with any chassis using AICS mags, just have the smith fit the chassis. I don’t want to speculate on added cost but it should be minimal.
According to the MDT website, you may have to make an adjustment to the claw extractor, anti-bind lug, or to their magazine (which will work without milling the receiver because they are narrower at the front than an AI mag). In a (PM) conversation with MDT_Josh, the likelihood of your having to do this is 100%.
I have an FNH A3G that's itching for this chassis. Someone needs to pull the trigger and get one and let me know if it was worth the time/mods/money to do lol. I recently had CDI install a DBM and its great but I kinda wish I knew about this a few months ago.
If you've already had your receiver milled, then there's no reason why your rifle wouldn't just drop in using other-than-MDT AI mags. The problems with fitment appear to come from using a CRF receiver with MDT's magazines.
Oh ok cool. I don't know much about this stuff. Thanks. I'll just pull the trigger on it and if it doesn't drop in, I'll find a good FN/M70 smith to do the work.
I'm basing my conclusions on the description on the MDT website and one single PM conversation with their guy on here. The way I read it, there is not any problem with the receiver fitting into their chassis (since it is inlet for the action), but that to avoid having your receiver milled (which you've already done), you'll have to use their brand AI-pattern mags. Problem is that by designing their mags to fit into the SPR/Mod 70 (by narrowing their mag's top front), they've created an interference with some part of the bolt which requires you to alter the bolt and/or the magazine's feedlips.
Since your action now accommodates standard AI mags, function should be unaffected by moving everything over to the ESS chassis so long as you continue to use the same-spec magazines.
I'd still like to put my SPR into an ESS chassis but since using 5 rd. AE Mk I mags (in PTG bottom metal) suits my needs for now, I'm not in any rush to beta-test for them.
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@M8541Reaper and @kl3309 thank you both for your interest in our chassis!
You are correct that the inletting is the easy part and any M70 will drop right into the chassis as it is just for the recoil lug, trigger and safety, but the magazines are the issues. If your rifle has been modified by a smith to accept AICS pattern magazines, you should have no problem running them in our ESS, in fact that is how we built this chassis (with an SPR that was modified for AICS magazines). The claw extractor and portion of the bolt interferes with the top of the right (looking from the back of the mag) feedlip and will cause feeding issues. Essentially, the M70 was designed around feeding from their mags, and when you adapt it for anything else, you will run into problems. This is true with a lot of actions (Browning, Ruger and Sako come to mind), especially those designed for hunting originally.
If you have any questions about modifying the action, magazines or chassis, feel free to contact me directly or our support team at [email protected].
Josh
You are correct that the inletting is the easy part and any M70 will drop right into the chassis as it is just for the recoil lug, trigger and safety, but the magazines are the issues. If your rifle has been modified by a smith to accept AICS pattern magazines, you should have no problem running them in our ESS, in fact that is how we built this chassis (with an SPR that was modified for AICS magazines). The claw extractor and portion of the bolt interferes with the top of the right (looking from the back of the mag) feedlip and will cause feeding issues. Essentially, the M70 was designed around feeding from their mags, and when you adapt it for anything else, you will run into problems. This is true with a lot of actions (Browning, Ruger and Sako come to mind), especially those designed for hunting originally.
If you have any questions about modifying the action, magazines or chassis, feel free to contact me directly or our support team at [email protected].
Josh
Thanks for the clarification Josh! So then I should be good to go with dropping my A3G into the ESS and shouldn't have an issue using my AICS mags (seeing as how its already been modified)? My whole thing was that I have been wanting a chassis setup for a while now but there weren't/aren't many options for the A3G (which is why I went with the CDI option). I'm just now faced with the question of do I drop the $1k on this chassis for the M70 and hope all works as it should and risk feeding issues...or do I sell the A3G as it is and invest those funds into a more common action that is guaranteed to work with the ESS?
I appreciate all of the feedback guys!
If you already have your AG3 running with AICS magazines, I don't see any reason why it wouldn't drop straight into our chassis
The choice is a hard one and we get it all the time, but the M70/SPR action is a very solid build in my opinion and I definitely have an inexplicable love for CRF, 2 lug bolts that just run. Either way, happy shooting!Josh
