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Manners Mini Chassis vs Bedding
- Thread starter Tony1320
- Start date
no difference at all. if there was all the benchrest guys would be bedding their rifles.
walk down the line and you will see all sorts of bedding and stock inlets.
what i like about the mini chassis or non bedding style, is that the bedding never cracks or breaks.
no matter how careful you are with a bedded rifle if you remove it enough times the bedding will start to chip.
happened on several hunting rifles that i would take all the way down because they were blued and walnut not stainless.
walk down the line and you will see all sorts of bedding and stock inlets.
what i like about the mini chassis or non bedding style, is that the bedding never cracks or breaks.
no matter how careful you are with a bedded rifle if you remove it enough times the bedding will start to chip.
happened on several hunting rifles that i would take all the way down because they were blued and walnut not stainless.
Idk, I wouldnt say there is zero difference. If it were a benchrest rifle I would say to bed it 100%, its the only way to guarantee a true stress free situation.
And I cant say Ive ever seen a real benchrest rifle that wasnt bedded. Well I guess glue ins and barrel blocks but I would still sort of count that in the bedded category as opposed to a chassis.
And I cant say Ive ever seen a real benchrest rifle that wasnt bedded. Well I guess glue ins and barrel blocks but I would still sort of count that in the bedded category as opposed to a chassis.
Benchrest guys do bed their rifles though, I come from F-Class where everyone does bedding
In PRS though I see a lot of the top shooters use chassis without bedding
What I've seen over the years.
First, the basic geometry/physics involved in this have to be understood. If you take a "V" and put a cylindrical object inside the two flanks that oppose one another, it will naturally find the middle and become supported wherever the "pipe" decides to lay tangent to it. Now, apply a load to that pipe by having two screws thread in from the bottom. What ends up happening is along the contact point/line the "V" tries to spread from the force. This is a great way to secure something as the "pinch" becomes really focused and it encourages things to stay put.
Where it all goes to shit:
The tang feature on a lot of actions has a geometry that emulates a broadhead on an arrow. Because it narrows the rear most contact point tends to reside in front of the rearmost action screw. When this happens, you end up with a lever. Demonstrating this is easy. Drop the front screw and tighten the rear. Doing so makes the front of the action levitate off the register. How this complicates things is if you snug up the front screw to 50lbs inch and do the same on the rear, you are basically making the receiver behave the same way a cat does when you pet it over its back. The action is now hunched up in an arc.
The mini chassis from MCS has gone through a few revisions over the years. Not sure exactly on dates, but changes have certainly been made. The rear hole now has a small "squish ring" feature. It's intended to support the bottom side of actions using a Remington type profile tang. It will deform slightly to the contour of the receiver when the screw load is applied. This is in an effort to thwart what I just described and it does work provided you don't go overly "bipolar" on the guard screw torque.
Legacy stocks did not have this feature. Bedding was one way to resolve the issue. I went so far as to surface machine the bedding blocks to offer a more mirror type register that would support the action across the entire circumference of the contact patch. This worked but had a whole lot of cascading effects. Magazines had to be dropped in the boxes, triggers started running into the guard frames, and the ports, bolt handle inlets also had to be adjusted.
The final solution I came up with was to drill/tap the rear hole, thread a brass pillar into it, then contour the pillar to the action's radius with a form tool I had ground special. I'd then just drop the tool down incrementally and take small passes until the pillar feature allowed the sides of the receiver to catch up with the tangent contact points along the sides of the chassis. Its worked really well and avoids all the drama of bedding and preserving a nice presentable finish afterwards. We don't do this service very often anymore so it's kind of obsolete I guess. -Likely because the newer stocks already have something very similar.
The point in all of this is ensuring were talking apples to apples. The devil is in the details here and its important to know exactly what it is you are working with. Older stocks vs new.
Hope this helps.
C.
First, the basic geometry/physics involved in this have to be understood. If you take a "V" and put a cylindrical object inside the two flanks that oppose one another, it will naturally find the middle and become supported wherever the "pipe" decides to lay tangent to it. Now, apply a load to that pipe by having two screws thread in from the bottom. What ends up happening is along the contact point/line the "V" tries to spread from the force. This is a great way to secure something as the "pinch" becomes really focused and it encourages things to stay put.
Where it all goes to shit:
The tang feature on a lot of actions has a geometry that emulates a broadhead on an arrow. Because it narrows the rear most contact point tends to reside in front of the rearmost action screw. When this happens, you end up with a lever. Demonstrating this is easy. Drop the front screw and tighten the rear. Doing so makes the front of the action levitate off the register. How this complicates things is if you snug up the front screw to 50lbs inch and do the same on the rear, you are basically making the receiver behave the same way a cat does when you pet it over its back. The action is now hunched up in an arc.
The mini chassis from MCS has gone through a few revisions over the years. Not sure exactly on dates, but changes have certainly been made. The rear hole now has a small "squish ring" feature. It's intended to support the bottom side of actions using a Remington type profile tang. It will deform slightly to the contour of the receiver when the screw load is applied. This is in an effort to thwart what I just described and it does work provided you don't go overly "bipolar" on the guard screw torque.
Legacy stocks did not have this feature. Bedding was one way to resolve the issue. I went so far as to surface machine the bedding blocks to offer a more mirror type register that would support the action across the entire circumference of the contact patch. This worked but had a whole lot of cascading effects. Magazines had to be dropped in the boxes, triggers started running into the guard frames, and the ports, bolt handle inlets also had to be adjusted.
The final solution I came up with was to drill/tap the rear hole, thread a brass pillar into it, then contour the pillar to the action's radius with a form tool I had ground special. I'd then just drop the tool down incrementally and take small passes until the pillar feature allowed the sides of the receiver to catch up with the tangent contact points along the sides of the chassis. Its worked really well and avoids all the drama of bedding and preserving a nice presentable finish afterwards. We don't do this service very often anymore so it's kind of obsolete I guess. -Likely because the newer stocks already have something very similar.
The point in all of this is ensuring were talking apples to apples. The devil is in the details here and its important to know exactly what it is you are working with. Older stocks vs new.
Hope this helps.
C.
I think one area where a bedded rifle will have an advantage over a chassis-mounted rifle is POI shift when disassembling/assembling the rifle. Accuracy differences between the two will always be debated and will always be difficult to test/analyze.
With a bedded stock, the receiver should sit in the same spot if it is removed and reinstalled, and there should be POI shift. A few weeks ago I had my rifle completely disassembled; scope removed, receiver removed from stock, and barrel removed from the receiver. When I reassembled everything I had no POI shift at 100 yards which I thought was impressive. This is with a traditional shouldered barrel, and skim-bedded Manners mini-chassis.
With a bedded stock, the receiver should sit in the same spot if it is removed and reinstalled, and there should be POI shift. A few weeks ago I had my rifle completely disassembled; scope removed, receiver removed from stock, and barrel removed from the receiver. When I reassembled everything I had no POI shift at 100 yards which I thought was impressive. This is with a traditional shouldered barrel, and skim-bedded Manners mini-chassis.
Hi guys, I thought I would repost some info I did a few years ago on the hide, note below. Thank you
The MCS-mini chassis is a V block design system, which in our opinion is the best design to fit the original purpose of the mini chassis. The original purpose of the mini chassis was to develop a high end drop in and go DBM system for a tactical/hunting stock with ability to be used with a wide varity of actions that did not require bedding. The key word here is “ wide Varity of actions”. Not just one or two highend action brands -, but a wide varity. This was the hardest part of the design. . Even actions from the same manufacture will not always be of the same diameter, shape, or even straight. To correct some of this difference, we designed the chassis so that it actually contacts the action in about six different points. First - the back of the lug area, Second/Third - about 1” contact on both sides of the action from the lug area backward, Fourth/Fifth – both sides of the tang area from the back action screw forward. Sixth, a small crush ring around the rear action screw. The reason for the crush ring is that not all actions are the same diameter and we want to make sure that the action is draw down and centered in the chassis. I would much rather have the action setting centered in a V block than one that is rocking side to side on the bottom of the action. In a perfect world the best chassis design would be a 100% machined, contoured, and matched fit to each action, but its not a perfect world.
I think what happens is that guy’s loose site on what the mini chassis was designed for. During the first test on the prototype chassis we took one of my older Rem 700 6mmBR guns and used it as a test bed. This gun will easily shoot in the very low .200” groups all day long. The first groups where shot in the fully bedded 100% carbon fiber bench rest stock. Then we droped it into an MCS-T4A with a mini chassis. The groups opend up about .100”. Was the .100” due to the chassis or because we went from a full bench gun riding in mechanical front/rear rests/bags, which was shot free recoil to a tactical stock shot off a bipod and a rear bag? Being a stock maker I got a pretty good idea on what caused the groups to open up, not all of the difference, but a lot was due to the way the two stocks ride the bags or lag of.
Bottom line is, do what gives you the most confidence in your rig. You can have a million dollar rig, but if you don’t have confidence in it, you aint going to hit shit. Some guys will bed the chassis just like they do a AI, others will do just the lug. But most ( 99% ) will just bolt it up and go. The chassis are proven shooters. Keep in mind the purpose of the chassis when I say, I dont think you are going to gain anything by doing a full bed job on a chassis, if you are building a gun that you plan on bedding, do a full pillar bed job from the start. When I build my own personnel guns, if it is a tatical comp gun I use a chassis. On the other hand, if I am doing a full blown F-class, or bench gun, where I am going to gain all the advantages of the stock and other equipment, I do a full stress free pillar bed job. Again do what gives you the most confidence.
The MCS-mini chassis is a V block design system, which in our opinion is the best design to fit the original purpose of the mini chassis. The original purpose of the mini chassis was to develop a high end drop in and go DBM system for a tactical/hunting stock with ability to be used with a wide varity of actions that did not require bedding. The key word here is “ wide Varity of actions”. Not just one or two highend action brands -, but a wide varity. This was the hardest part of the design. . Even actions from the same manufacture will not always be of the same diameter, shape, or even straight. To correct some of this difference, we designed the chassis so that it actually contacts the action in about six different points. First - the back of the lug area, Second/Third - about 1” contact on both sides of the action from the lug area backward, Fourth/Fifth – both sides of the tang area from the back action screw forward. Sixth, a small crush ring around the rear action screw. The reason for the crush ring is that not all actions are the same diameter and we want to make sure that the action is draw down and centered in the chassis. I would much rather have the action setting centered in a V block than one that is rocking side to side on the bottom of the action. In a perfect world the best chassis design would be a 100% machined, contoured, and matched fit to each action, but its not a perfect world.
I think what happens is that guy’s loose site on what the mini chassis was designed for. During the first test on the prototype chassis we took one of my older Rem 700 6mmBR guns and used it as a test bed. This gun will easily shoot in the very low .200” groups all day long. The first groups where shot in the fully bedded 100% carbon fiber bench rest stock. Then we droped it into an MCS-T4A with a mini chassis. The groups opend up about .100”. Was the .100” due to the chassis or because we went from a full bench gun riding in mechanical front/rear rests/bags, which was shot free recoil to a tactical stock shot off a bipod and a rear bag? Being a stock maker I got a pretty good idea on what caused the groups to open up, not all of the difference, but a lot was due to the way the two stocks ride the bags or lag of.
Bottom line is, do what gives you the most confidence in your rig. You can have a million dollar rig, but if you don’t have confidence in it, you aint going to hit shit. Some guys will bed the chassis just like they do a AI, others will do just the lug. But most ( 99% ) will just bolt it up and go. The chassis are proven shooters. Keep in mind the purpose of the chassis when I say, I dont think you are going to gain anything by doing a full bed job on a chassis, if you are building a gun that you plan on bedding, do a full pillar bed job from the start. When I build my own personnel guns, if it is a tatical comp gun I use a chassis. On the other hand, if I am doing a full blown F-class, or bench gun, where I am going to gain all the advantages of the stock and other equipment, I do a full stress free pillar bed job. Again do what gives you the most confidence.
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I have had NO POI shifts w HS Precision stocks w the bedding block system design. As fare as accuracy i found Chassis, bedded stocks and stocks w a bedding system or mini chassis all being equal. All have produced .5 moa or less w 20 shot groups on my rifles. Action screw torque specs are very important.
Not from my understanding as the Mini Chassis is installed into the stock during the building. You might want to check with Tom to make sure but I would say no.
As to accuracy difference, I don't see one. I have my first Manners T3 I got on my original 6.5 Creedmoor in 2008 and it's bedded and I also have a few with the mini chassis system and they are all equally accurate rifles. I would recommend the mini chassis system to anyone buying for an action that it will fit as it's very easy to drop in and torque down and you get a DBM and a barricade stop option.
I see no POI shifts in my Mini Chassis rifles when I remove the barreled actions from the stock and reinstall. No bedding. Just bolted in.
I'm sure my mini-chassis would have shot great without any skim bedding, and I guess I can't really make an assumption of POI shift of a chassis rifle vs. bedded rifle, since I have never done a direct comparison. Clearly the MCS mini-chassis is well designed.
In my case, the only reason I had the mini-chassis skim bedded was cause my rifle was at a gunsmith for another reason, and I just decided that I would get it done while it was there for peace of mind (or whatever it is that I was after, lol).
In my case, the only reason I had the mini-chassis skim bedded was cause my rifle was at a gunsmith for another reason, and I just decided that I would get it done while it was there for peace of mind (or whatever it is that I was after, lol).
Here is the message directly from Tom to me yesterday. As I see it, installing the mini-chassis is the very last step before they ship 'em on out.
Hi Don, I just left you a voice mail, here is recap
I noticed Robert from the office posted on the thread this morning, before I was able to get my hands on it. I just went back to the finish room, everything is finished out, they are just installing the chassis now, that's the last thing to be done. I am going to do my best to get it on its way to you actually today. I should have a tracking number for you by the end of the day. I will pm that number to you. Thank you
That would be nice if they could retrofit stocks with them but not sure if just because it goes in last means they can do a retrofit. Wonder if Tom or Rob could fill us in on that.
Hi Guys, There are a few difference's in the construction and process steps between a bedded and mini chassis stock. We can still take a used stock that has been pillar bedded and install a mini chassis. This is usally not a problem in most cases but will depend on the original trigger guard inlet. If your original stock had a surgeon or wider bottom metal that has a show line bigger than the mini chassis, it will need to be filled and finished. This is not a big deal on a painted stock, they get a complete new finish anyway, on a elite, we will do our best to blend that area in. M5 inlets require just a hair of fill around the front action screw area maybe .050", factory bdl and smaller trigger guard inlets get cut out and cleaned up 100%.
The mini chassis install is usually one of the very the last steps in the process. This is basically done so the finish of the chassis is maintained and not messed up during the stock finishing process.
Thank you
