Case Trimmer Lessons Learned

My experience is based on straight wall brass for handguns. My desire was for consistent length so a roll crimp would always hit the same place on my boolits. I do not trim my brass for my taper crimped auto loads.

I started with the basic Lee trimmers and their Zip Trim with the three jaw chuck. That worked reasonably well for the limited cost involved. However, the lengths varied enough to cause problems with a consistent roll crimp. Next I moved up to a Redding 2400 Match Precision Case Trimmer. My decision was based on perceived quality and the manufacturer's marketing info. The lengths were a little more consistent, but they still varied enough to cause problems with roll crimps. My son-in-law uses another brand with a collet style case holder and has the same problem with inconsistent lengths. So much for the old theory that you get what you pay for. The great difference in price really didn't make much difference in the end result.

After a few months with the Redding, I gave up and purchased a Sinclair/Wilson trimmer with their Q-style shell holder. Now I can trim my .357 brass to a consistent length. As usual, my education was not free. I hope someone can learn from my experience instead of shelling out money to learn.

Been loading straight walled pistol shells since the mid 1970's, never trimmed one. Never had a problem with a roll crimp. I do trim bottleneck hulls.

Have a blessed day,

Leon

The technique used with any trimmer will determine the consistency of the cut. A couple trimmers on the market are such poor designs as to virtually defy an accurate or consistent cut.

I've experienced inconsistencies with collet type trimmers. hen I used one I would try to tighten the collet the same each time. I've been very satisfied with my Wilson trimmer as all tricked out by Sinclair. With the carbide cutter, its a pleasure to use.

On another note, years ago I started trimming bottle neck cases with the Lee case gauge/cutter and found them to be consistent. Not the universal chuck, the stud with shell holders. They can be a pain sometimes.

I have had the same experience as lightman with trimmers. I do all my trimming with Wilson and use the Q type holder for .38 & .44.

Ill echo the sentiments on the consistency of your process, that is the key point regardless of what tool is used. Of course some tools are better than others but good results can be had.

I started out learning with a hand me down Lyman universal with a wobbly cutter shaft. If I took my time I learned my process to consistently trim all my cases that came out fairly consistent and square. Thru a good stroke luck I tripped into a deal on a Forster set with all of the collets and a good collection of pilots/adaptors included. Another process learning curve but once I got it down I can now consistently cut any case square and to length.

I like my RCBS Trim Pro. Had a collet style that supposedly "fit" all sizes but couldn't get consistent with it.

I can't comment on trimming pistol cases as I fall into the "Why Bother" camp. (But if it works for you, then it is the right way) But I do have an opinion on your choice of trimmers. When I started to reload in the mid 60s, I needed a trimmer for the 30-06 I was shooting. Shooting pick up cases of mixed vintage, my case lengths were all over the place. I read all I could find about trimmers and went to my local shop to ask what he would recommend. His answer was: "I will sell you my Wilson trimmer and a 06 holder for". (I think 10 or 15 bucks). I am still using it. I have replaced the cutter and added a power drill adapter along with many other shell holders(including several pistol case holders, which I have yet to use) Still works great and I suspect it will be working for the next guy who owns it long into his senior years. You made a good choice!

One of the problems with collet type holders is that small differences in rim dia cause the collet to grip out farther or in farther. Its the nature of the beast. The Wilson holds and centers the case with the body and is then set against a dead stop, locating the case much more accurately. The collet type do a good job if rims are clean, burr free, and all the same dia. .002 rim dia vatience on the collet makes a difference in how deep the collet seats into the mount.
To make the collet more accurate for length the collet should be fixed and the sleeve move to lock it.

Interesting. I never trim pistol cases but see how it could affect crimp consistency and thus accuracy.

I know that Star made a taper crimp die for the .38 Spl and I suspect it was to address that problem. Likely a taper crimp is not ideal for a heavy recoiling round that goes into tube magazines (think .44 Mag in a lever action).

I cannot shoot a pistol even half as well as I used to...so that may be a blessing. The thought of trimming the 3000+ .38 cases I have is repulsive.

But If I wanted to do it, I would use a drill press mounted fixture. It would allow the same cartridge length regardless of rim thickness or rim condition; as it would reference on the bottom of the case.

I use an RCBS Trim Pro for rifle and think it would work for rimmed pistol cases as well. I do not see how rim thickness would affect it.

My Wilson trimmer is very accurate and consistent. I also found the Lee trimmer to be very accurate, finding the lack of any sort of length adjustment its only fault. The Wilson and the LEE vary less than .001" from case to case in my hands. I have a Forster collet trimmer, but .002-.003 was the best I could normally get with it. Haven't trimmed handgun cases, .38 Spl, .357, 44's, 45's, .380 or 9mm. I am careful to keep cases separated by make and times fired. Most of crimping is on 30-30, 32 Spl, 35 Rem, 444, 45-70 for tube magazines, where trimming keeps the crimp very uniform. I trim other rifle based on uniformity within 50 or 100 cases. trimming all to the shortest. I have checked chamber length on multiple rifles, finding factory chambers very long in most cases - .015+ or more.

Pull collet trimmers will cause cases to vary with variations in the rim diameter.
Shell holder type trimmers cause cases to vary with differences in rim thickness.
The Forster trimmer has push collets that will give repeatable results.
I own several Forsters and prefer them over other brands. I also own several Wilson trimmers and they work ok but require more care to insure the case holder does not move while cutting.

I have one of the old RCBS Trimmers, that uses 4 different stepped collects, 40+yrs and it's still doing It's job very WELL.
I've found that maintaining the same lots of brass leads to consistent case length. If you trim 4 or 5 different brands of cases, then you will get inconsistent case length because you have different rim thicknesses.

I bought a LYMAN powered case trimmer 25+yrs ago, the same rules apply.

Maintain your brass in the same lots you buy them in, and you will be able to get consistent case length.

im with old joe don't trim straight cases anymore just bottle neck.

Quote:

---

Originally Posted by EDG

The Forster trimmer has push collets that will give repeatable results.
I own several Forsters and prefer them over other brands.

---

The Forster collets are multicartridge and you can tighten down the collet to early. I’ve done this to often and ruined cases. Happened w/ one particular cartridge so much that I had them make a custom collet. No more issues now.

I own three Forsters and they’re a versatile tool but they have quirks like any tool. You will get repeatable results if your technique is consistent.

As far as trimming straight wall cases. I will simply say if the cartridge requires a roll crimp you will see a benefit by trimming them to a consistent length. This is visible on target and over the chrono.

I believe the Wilson system is the best! The trimmers that fix the brass at the base have a tolerance, even if minimal. Perhaps the shel holder Lee, with the threaded pin that pushes the brass up to lock it works better.
I have the Wilson trimmer (stainless - micrometer) to bring all the brass to the same length: to be honest I thought to do the trim also on the case back case to see if it was perfectly level! I have also the Lee!
To get my neck back, I have the Hornady, the same to check the concentricity of the bullet.

I found the micrometer on the Wilson unnecessary. I use both a standard pre trimmed case or a case length gauge to set trim length. That's about the only real use for case length gauges I've found.:bigsmyl2:

i use the hornady trimmer and it is very constant usually no more than .001 difference. but it has some draw backs you must buy hornady shell holders as no others will work and it will not do all calibers ( found this out the hard way ). but for what you can use it for it does work great but knowing what i know now i would go another way spent more on new shell holders than the trimmer.

I have owned Wilson(still have one), Lyman(sold), RCBS(sold), Pacific(still have one), and C&H(still have 6). Gradually over the years I have acquired one for each rifle caliber that I load ammo and 1 for each pistol caliber I load. Of the ones I have owned, I still prefer the C&H as it uses the same shell holders as the Wilson and does just as good of a job and costs about half what a Wilson costs. They both will trim to length dead on settings. I do use Q style Wilson holders on my revolver calibers. They all got the job done but the collet style does have small variation according the rim thickness and or rim damage cause of slam-o-matics(semi autos). my experience anyway, james

Quote:

---

Originally Posted by PJEagle

My experience is based on straight wall brass for handguns. My desire was for consistent length so a roll crimp would always hit the same place on my boolits. I do not trim my brass for my taper crimped auto loads.

I started with the basic Lee trimmers and their Zip Trim with the three jaw chuck. That worked reasonably well for the limited cost involved. However, the lengths varied enough to cause problems with a consistent roll crimp. Next I moved up to a Redding 2400 Match Precision Case Trimmer. My decision was based on perceived quality and the manufacturer's marketing info. The lengths were a little more consistent, but they still varied enough to cause problems with roll crimps. My son-in-law uses another brand with a collet style case holder and has the same problem with inconsistent lengths. So much for the old theory that you get what you pay for. The great difference in price really didn't make much difference in the end result.

After a few months with the Redding, I gave up and purchased a Sinclair/Wilson trimmer with their Q-style shell holder. Now I can trim my .357 brass to a consistent length. As usual, my education was not free. I hope someone can learn from my experience instead of shelling out money to learn.

---

Little things are what make up ultimate accuracy. For plinking, nobody cares much about accuracy. But for match shooting and match quality loads, uniform case length is just the ticket for uniform crimp on straight walled handgun cases.

You struck gold when you acquired a Wilson lathe type trimmer. You can keep a trimmed case and use that time and time again to set the trimmer to the same length again. I add an additional nut on the trimmer to lock it into place. I use the old press in case holder, but the Q type works just as well.

I have been using the same Wilson trimmer since 1959 and only last year had the cutter sharpened by Wilson. If you are looking for fast, Wilson is not your trimmer. However, if you are looking for uniform accuracy and repeatable length, it is the huckleberry.

Another vote for the Wilson trimmer!

I do my heavy trims on a Lyman universal and the final pass on the Wilson on over length bottle necked rounds. I bit the bullet several years ago and bought a carbide cutter for the Lyman trimmer.

Three44s

You might tighten the case on the wrong step but you would not be paying attention. Most of the steps are far enough apart that you can't get the collet to grab the case head with the wrong step.
The benefit of the Forster collets is that you can trim almost all cases with only 3 collets. Did you ever price 50 Wilson case holders?
There are many calibers that I shoot for which Wilson makes no holder.

Quote:

---

Originally Posted by dragon813gt

The Forster collets are multicartridge and you can tighten down the collet to early. I’ve done this to often and ruined cases. Happened w/ one particular cartridge so much that I had them make a custom collet. No more issues now.

I own three Forsters and they’re a versatile tool but they have quirks like any tool. You will get repeatable results if your technique is consistent.

As far as trimming straight wall cases. I will simply say if the cartridge requires a roll crimp you will see a benefit by trimming them to a consistent length. This is visible on target and over the chrono.

---

Quote:

---

Originally Posted by EDG

You might tighten the case on the wrong step but you would not be paying attention. Most of the steps are far enough apart that you can't get the collet to grab the case head with the wrong step.

---

It is possible which is why I pointed it out. It happened mostly w/ 308 brass. Which is one of the most common cartridges.

I find the Wilson trimmer to give the most consistent length and the most square mouths of my trimmers. If I don’t have or can not get a holder for a particular cartridge from Wilson I settle for my Lyman universal trimmer and that is that.

I also have the Forester trimmer but I primarily outside neck turn with it and the RCBS trimmer that uses collets. I bought that one off the net used because I was intent on setting up their one pass chamfer, debur and trim head which I have not around to yet.

I have been so happy with the consistency of the Wilson system I have been concentrating on it.

As far as acquiring the holders, I have thus far been relying on estate pick ups so far. I think I need to buy or find only two or three more holders at this point.

The other point is that one can prioritize which holders one buys and start with your most accurate cartridges. I am more intent on having holders for my “minute of fly” varmint guns for instance. Many other holders have filtered in and they are saved even if I don’t shoot that round yet. One just never knows when you are a gun crank!

I have not gotten into my handgun rounds with the Wilson yet as I have not felt a bit of mouth variation is as critical there ....the Lyman universal carries the ball there.

Three44s

WFT is the trimmer I use and it's very accurate and quick.

Quote:

---

Originally Posted by dragon813gt

It is possible which is why I pointed it out. It happened mostly w/ 308 brass. Which is one of the most common cartridges.

---

You can use a strip of wood (Popsicle stick) to press against the pilot tip and the cartridge case neck. You place the case in the opened Forster collet and press the pilot toward the case neck to seat it fully in the collet. You then tighten the collet, remove the stick, and trim. IMHO the Lee pilot on Lee's Universal chuck is so much faster and you don't have to measure anything to ensure the correct cutting length. While the case is in the chuck, you can also chamfer & polish it as well.

I modified a lee to be adjustable for length. Drill and tap a 8 32 hole thru the 1/4" hex and base. make or obtain 2 8x32 flat point set screws. run in to base flat point up One is the stop for the pin the other locks it in place. You can now adjust the stop porting on the chuck base to cut shorter with out modifying the pin. You can cut a little longer but you need to "open" the case holder more to get cases over the set screw setting proud. #8 screw is around .160 dia so it will fit in primer pockets also. A little rough to adjust but can be handy if you need it.