question for wilson trimmer users

[nra-for-life]

when you check your trimmed brass with a caliper what tolerance are you getting your brass trimmed to???

i am getting some variation of +- .0015 and it seems like this is a lot.

 

[K22]

That does seem like a lot for a Wilson trimmer. Couple things to check,

1. Make sure that the case is not turning in the collet while your trimming.

2. Make sure that you have "bottom out"on the cutting cycle, i.e did not stopping prematurely. Sometimes I'll get excessive variation because of this especially when I'm trimming a lot of cases and I lose focus.

3. Make sure the set screw on the length adjuster is tight.

I found the Wilson to be the most accurate and uniform trimmer I've ever used however I purchased the Sinclair upgrades, i.e. the holder and carbide cutter which makes it easier to use and produce more uniform results.

To answer your question specifically, now don't laugh, I measure my case lengths with a Veriner Caliper, which reads only to .001". This caliper has no dials or digitals displays but is accurate (had it checked with gage blocks). I know, I'm still in the stone age but if it works don't fix it. I set the caliper for the trim length and used it as a "go gauge". I check each case after trimming and the trim lengths are very uniform as long as I follow the proper trimming procedures.

It's hard for me to imagine that a + or - .0015 variation in case length would affect performance however I'm not a bench rest shooter but I do strive for 1/2 moa accuracy since I'm a varmint hunter.

 

[bozo699]

when you check your trimmed brass with a caliper what tolerance are you getting your brass trimmed to???

i am getting some variation of +- .0015 and it seems like this is a lot.

nra,
If you have the Sinclair case holder clamp, make sure you put it over the case holder in the direction that would drive it up tight against the stop, it is easier to go the other way and some people do, this tends to pull the case away from the stop, make sure the case is tight in the case holder s it doesn't spin in the holder, Keep the brass chips cleaned up in the channel, don't let it build up, try to make sure the brass has been f/l sized before trimming as to keep all the brass uniform, hope this helps some.
Wayne.

 

[K22]

Excellent point by Bozo699, brass must be full sized to use the collet properly - see your instructions with trimmer. If not done, the collet won't hold the case properly and it will spin giving you erractic results.

 

[nra-for-life]

a picture is worth a thousand words so a video must be worth a couple ten billion or so i guess...


i cant figure this out and it is going to drive me insane.. here is a quick vid of 4 cases being trimmed....the last case is short after trimming ...wtf?

 

[6BRinNZ]

I found that slight pressure changes on the handle end could trim an extra .001" off.

What I do now is set up the Wilson so that the case is cut to length with my greatest amount of inwards hand pressure. Basically I start the micrometer slightly long and "inch" it in, trim and then check the case length. For this step I don't remove it from the case holder when I measure to speed things up.

Once the initial setup is done I basically trim and measure as I go. If I don't use the same amount of hand pressure the case will be longer (as the setup is intended to err on the long side meaning no wasted short cases) and I can then simply place back into the trimmer (its been in the case holder the whole time) and re-trim the .001" or so off.

I have also found that rotating the case seems to let the blades find a little bit more to cut...I don't rotate the case in the trimmer any more.

Hopefully this makes sense.

Good luck

 

[nra-for-life]

I found that slight pressure changes on the handle end could trim an extra .001" off.

What I do now is set up the Wilson so that the case is cut to length with my greatest amount of inwards hand pressure. Basically I start the micrometer slightly long and "inch" it in, trim and then check the case length. For this step I don't remove it from the case holder when I measure to speed things up.

Once the initial setup is done I basically trim and measure as I go. If I don't use the same amount of hand pressure the case will be longer (as the setup is intended to err on the long side meaning no wasted short cases) and I can then simply place back into the trimmer (its been in the case holder the whole time) and re-trim the .001" or so off.

I have also found that rotating the case seems to let the blades find a little bit more to cut...I don't rotate the case in the trimmer any more.

Hopefully this makes sense.

Good luck

hey 6BRinNZ, are you mindfull to keep the same side of your case (and case holder) in the same direction or does that not matter? (E.I.- the same side up as when it was trimmed the first time?) I wonder if having the power adaptor and using a drill would take away from this pressure variation you get when manually spinning the cutter.??

I have also noticed that if you rotate the case (and case holder) the trimmer will sometimes take more off.... why us this?? the only explanation i can come up with is that the bottom of the case is not square or that the trimmer cutter is not square.

 

[bozo699]

NRA,
I watched your video last night but was too busy at work to reply, I noticed a couple possible things

#1,.. get a piece of hard plastic a inch thick or so to pound your cases in and out of the holder, you don't have them seated in the holder hard enough IMO

#2,.. When your putting the case holder into the lathe your flipping the clamp over the case holder with your finger,....it's way to loose you should have to hold to holder and with some pressure slide the clamp over the holder

#3,...It probably doesn't matter but just in case there is a little miss alignment in things I always put the Wilson name facing me, I set up the cut that way and always put it back in the same way.

#4,...I do as 6BRinNZ I put as much pressure as I possibly would upon set up so if anything there long not short,..it's alot easier to remove more then weld it back on ;D

#5,..Last but not least I have both new and fired case holders for almost everything I have but I try to always f/l size my cases and bump the shoulder .001,... I have noticed if I trime then size I get some case length variance but no variance if I size then trim, I hope this helps some and if I think of anything else I will let you know or if you have any questions ask away.

P.S Your bench is almost as messy as mine, not quite but almost, you do know good loading practices start with good house keeping ,..you do have some nice stuff,..take care.
Wayne.

 

[nra-for-life]

hey wayne....

thanks for the input, i will try your suggestions and hopefully see some improved consistancy.

yeah i know my bench is a mess right now. i am out of room and i need to add some shelving etc.


so i have about 30 trimmed cases that are short. i have them categorized by size. the shortest ones are about .002 short of the trim length in the sierra manual. will those be okay to use??? if so...how will they likely affect accuracy? will they re-strech out after multiple firings where i could trim again to a normal spec??? Thanks

 

[bozo699]

hey wayne....

thanks for the input, i will try your suggestions and hopefully see some improved consistancy.

yeah i know my bench is a mess right now. i am out of room and i need to add some shelving etc.


so i have about 30 trimmed cases that are short. i have them categorized by size. the shortest ones are about .002 short of the trim length in the sierra manual. will those be okay to use??? if so...how will they likely affect accuracy? will they re-strech out after multiple firings where i could trim again to a normal spec??? Thanks

NRA,
No problem, I am always happy to help and be helped, next tim it may be you helping me.

I have a heck of a time keeping my loading room tidy, but I know it is important to do, there is never enough room ???

.002 isn't going to hurt anything, do as planned, keep them separate and shoot them as a set and when they stretch trim them to the proper length.
Wayne.

P.S no one is more precision minded then I am but people like you and I tend to go overboard, if there within .0005 I would say there probably pretty good,...open your caliper up .0005 and hold it to the light and see how much daylight you can see, it's not much! and one other thing I noticed in the video make sure you use the same pressure and the same measuring point on the caliper each time

 

[lpreddick]

just an observation: when i trim just a few thou, i don't have to turn the cutter nearly as much as in the video. my trimming platform is on a wooden table and i can hear when trimming is complete. is a dull cutter possibly a problem? also noted, annealed brass really trims differently than non. agree that .0015 variation can occcur with additional pressure on comperator. l love my wilson trimmer and the little white plastic disc for tapping case into and out of holder is probably better than tapping on table, or hand...ouch.

 

[bozo699]

You know NRA's Idea of the video is just about as good of idea as I have seen, I may try to figure out how to do that and post it when I am having a problem so others can evaluate it, sometimes one can't see what he is doing wrong but others that are standing back and aren't frustrated can see clearly what the problem is. A few years ago I started shooting poorly, my groups just plain went to hell and I couldn't figure it out ??? I video taped myself shooting and figured out I had developed a flinch from the noise, I had to use better hearing protection and really concentrate to get over it as a matter of a fact that was years ago and I still have the problem if I don't stay on top of it, a video really is worth a 1000 words Great thinking nra-for-life
Wayne.

 

[Cigarcop]

My fingers hurt just watching the video....do your hands a favor and get a 4V Ryobi from Home Depot...turns at the perfect speed and is the right height for the job.

 

[bozo699]

My fingers hurt just watching the video....do your hands a favor and get a 4V Ryobi from Home Depot...turns at the perfect speed and is the right height for the job.

I don't mind turning my Wilson by hand but I wouldn't be without my Ryobi 4V cordless screwdriver in my loading room, what a great little tool, I don't usually like Ryobi tools as they tend to be cheap but this has been a great tool and has held up great, mine is a older version that doesn't have the removable battery pack like your's does and my battery is starting to fade, when it goes south I will go to home depot and replace it with the new version
Wayne.

 

[jlow]

Having used a similar setup for a while and having had lots of problems with it, I would urge you to be very careful to not put any pressure on the power take off shaft that is not directed forward as it bends very easily and then the whole thing will be out of wack.

 

[bozo699]

NRA,
I trimmed 100 6brx cases tonight and really played around to find where your troubles may lay and I am glad I trimmed shallow so I could go over them again for a final trim, I found it to be the most consistent when everything remained consistent, I kept the clamp tight and over the holder in the same place every time, I kept my hand off the holder while turning (that made a difference) I turned the crank exactly 10 revolutions each time and the same pressure every time! even when I re-oiled the cutter shaft it made a difference, I was able to keep it within a .0005 on most cases when I applied these techniques they stayed pretty consistent but if I varied so did the measurement, I hope this helped some more, if you only change a couple things tighten up the clamp and KEEP your fingers off the case or case holder while trimming because there is a tendency push on it and it WILL take more off!! for those who don't have the clamp and you have to hold the case holder by hand hold steady pressure against the stop.
Wayne.

 

[lurcher]

Are you using the sharkfin clamp to hold the case holder Wayne? I've never been entirely happy with mine it doesn't seem to be that steady and I get some chatter

 

[bozo699]

Are you using the sharkfin clamp to hold the case holder Wayne? I've never been entirely happy with mine it doesn't seem to be that steady and I get some chatter

Lurcher,
Yes it is the sharkfin and unless you have some pressure on it, it isn't consistent, I have a friend with a camover type clamp on his and I haven't used it much but I think I would like it much better.

 

[tripcrow]

Try measuring the OD of your caseholder on both ends with a micrometer. If one end is larger than the other the case isn’t being trimmed perpendicular to the case axis. So when you go to measure the trimmed case the reading will depend on how you hold the case while measuring. The uneven holder really shows up if you also use the Wilson Uniform Deburring Tool. I guess it is also possible that the hole is off center too.

 

[zfk55]

I have it mounted on a 4" x 3" square aluminum tubing to make it absolutely solid. I use left thrust with my left hand and get zero variance, right to the thousandth.