Do these things [recoil buffer] work? Has anyone tried one, I seen them for sale, nylon & no doubt printed with 3-D printer.

I've tried them in 1911s but not in my 41. I am not sure they serve any useful purpose in any gun.

Unless you plan on feeding a 41 a steady diet of HV ammo they're a waste - IMO!

My 41 is unreliable with standard velocity ammo (including CCI) so I use CCI MiniMags. After reading that long term use of high velocity ammo might eventually cause the trigger guard to break I bought one of the buffers.

I am guessing I have put about 2000 to 3000 rounds through the gun since I started using the buffer. It is hard to prove a negative so there is no way to tell if it has prevented any damage. But it certainly has not caused any malfunctions or other problems and is holding up well.

I suspect that most model 41s, including mine, will never be shot enough to be damaged by high velocity ammo. But the buffer was inexpensive and the peace of mind I get from using it is worth more than what I paid for it.

If you only shoot standard velocity ammo through your gun I wouldn't bother with a buffer. But if you regularly shoot high velocity ammo and are worried it might eventually crack the trigger guard get a buffer.

A recoil buffer must be made of a material that will not break apart or crumble under heat and impact

I would NEVER put a 3D printed buffer in any of my firearms

That being said, the only 22s that I put a buffer in are suppressed firearms. I do not do this to reduce wear and tear, I do it to reduce the sound of the action cycling.

I do use a buffer in my 10MM Auto conversions of Smith & Wessons. This is for the 1014/1013 pistols along with the CS10 conversions. I believe these are necessary considering the alloy frames

When I use a buffer, I use the Buffer Technologies products. The late Larry Bullock, founder, was a great innovator. Many/most of his buffers are patented

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"Acta non verba"

The typical buffer is made of some semi-soft elastomeric product. They are designed to "give" a little each time they are impacted with solid pieces of the gun. Over time in use they will wear out and must be replaced. Some failures will put the gun out of operation until the gun is disassembled to remove the buffer fragments.

A few guns, such as the Browning Buckmark, come from the factory with a buffer.

Spring rate (poundage) has a lot to do with semi auto pistol function and wear. The 1911 guys make a serious study of this. Primarily it's the recoil spring however the hammer spring plays into the equation a little.

If you need to shoot high velocity ammo, there are better guns than a 41. I use CCI SV in mine, about a '57 or '58 model; function and reliability is perfect and they're fairly accurate as well, but I'm not a competitor.

I purchased one for my new Model 41. Expensive for a cheap part. They should be 50 cents.
Have not installed, and been running HV ammo primarily, less than a 1000 rounds so far.
Mine came with no instructions, assume it goes over the guide rod.
Btw, purchased a brick of CCI SV. Ran a 100 of these. Did not seem any more accurate, cleaner, or softer shooting. At 65.00 a brick delivered from CCI, will stick with the cheap HV in attic for now.

I gather the general consensus is "can't hurt, might help / cheap insurance".
It shouldn't be necessary as the design worked well for decades without, but if your recoil spring is a little weak or your ammo is a little strong it's nice to know you aren't battering things too badly. I don't recall anybody saying they made the weapon less reliable or damaged anything.
I think they are more important in the 46 because of the lighter and weaker slide design.
Yes, if one broke in just such a way it could put the weapon out of service for a couple minutes while you field-stripped it, but it's not like you are using a 41 for social situations so that's not an issue.
Regarding HV ammo, the 41/46 does have a removable breechblock in the slide and given enough rounds, that block can loosen up in the slide with undesirable results. Will I run HV ammo without cringing, sure. Do I prefer to run something SV, yes. Actually FWIW I've sort of settled on Federal Automatch as a good medium round that the 41 seems to like very well in terms of accuracy and reliability.

They work for the fellow that sells them - they make money! LOL Seriously, I have owned my M41 since 1979, shot tens of thousands of rounds through the gun, never used a buffer and have had zero issues. That tells me there is no need for a buffer. I also believe if a manufacturer feels the need a part is warranted in their product, it would have come with the gun - at least back in the era I purchased mine in. Since it never came with a buffer I see no need to second guess the design.

Same goes for all my 1911's - never used them and after ten's and ten's of thousands of rounds of 230 grain hardball - no problems at all.

I bought a couple of Buffer Technology buffers for my 41 back when Brownell's stocked them. I like them. It actually silences the operation of the pistol somewhat, and are they necessary, probably not. But if the pistol functions ok with them I don't think they can hurt anything. I will say that with the buffer installed it seems that the slide just barely has enough travel to allow the slide stop to work on the last round, but it does. As long as the two that I bought lasts, I will be using them.

The proper ammo for a model 41 CCI .22 LR SV
But during ammo shortages one at times can not find it. So people do other things like putting a drop of lubricant on the top cartridge in the mag. And yes with time doing this will batter a model 41. You see one that has regularly been fired that way for years at matches and you can see that battering. I know someone years ago that got a call from Smith and Wesson and he was told to only used CCI SV in his gun. I gather that it was sent in for repair.
I hit this forum because I was going to buy a replacement buffer for my model 41. At the moment I am shooting the proper ammo, but still see no harm in using one. My current buffer has been in my pistol a while and I was using some federal auto match that is a hotter load than the CCI SV ammo.
The guys that were using the oil were shooting mostly aquila sv that will not operate the slide of a 41. If I clean my gun say every 6 wks or so function is 100%.

absolutely NOT...you calibrate the gun by using the correct recoil spring, 1911 or 41 or any other. You look if it cycles properly and how far the brass flies. I run a 7.0 lbs in my model 41 with SV ammo. I run the Volquartsen gold spring in my Ruger Mk 4 when shooting mini mag.

I see you say SV ammo. Which brand of SV ammo because they are not all the same.
By the way using a heavier spring is another way of using a buffer, except the slide closes forward with more force.

The absolute best course is to use what smith and wesson designed the gun to use. I have a new factory spring ordered because after more than 20 years it might be good idea to change it out.

I have a buffer in my M41 Smith as I plan to shoot HV in it. Don’t do bulleseye. Also have them in my Ruger mini30.

There are people that will put more than 30,000 through a model 41 in a life time of shooting. Maybe only 2-3,000 rounds of HV is ok.

When I first bought my M41 in 1979 I did shoot a few thousand high velocity (Winchester and Remington promo stuff) rounds through it - no damage to the gun what so ever.. When I got into the quest for a more accurate round, I found the CCI standard velocity to be the ticket. Until this day, the std. vel. CCI continues to be my round of choice in my M41. At least for me, I have not found any other round that is more accurate or functions better.