Trimming & Deburring

[fariaguard]

New to reloading using a Redding T7 Turret Press. Will be reloading pistol and rifle brass.

Just ordered the Sinclair / L.E.Wilson Stainless Ultimate trimmer w/ micometer to trim brass. Not the cheapest but it makes the most sense for my OCD relationship with repeatable accuracy.

As a newbie my question is this. As the case is trimmed does this trimmer also de-burr the outside of the case mouth? I would rather hear from my peers than get an answer from customer service trying to sell a part however I must say Sinclair has been awesome so far. Sinclair does sell a separate handle for this trimmer that will de-burr (chamfer? not sure on terminology the inside of the case mouth).

When do I need to trim my brass. When using the resizing die does it not re-size the case to the proper length?

I'm just now reading about full length, shoulder and neck resizing so I'm guessing it will have something to do with this.

I also just ordered the reloading DVD from Redding so my questions may be premature.

Thanks as always!

 

[1stmar]

Not familiar with the Sinclair trimmer but likely doesn't debur and trim in one step. Most people, myself included do not trim pistol cases.
Most companies in the shooting industry are very respectable and will give you the right info and not just try to sell you something. Presumably you are ordering from brownells. They are excellent to deal with.
When you resize a case it doesn't trim. It pushes the shoulder back (bottleneck) and resizes the mouth and body of the case back to specifications. This process also stretches the cases hence the trimming process.
You don't need to resize after every firing. Usually every 4-5 but it varies. You'll need to measure to determine.
Neck sizing is/was thought to be preferable to full length sizing for several reasons. For one, it doesn't work the case as much and brass life may be longer. It was also believed that since the case was fireformed to your rifles chamber it would provide some accuracy advantages. Though this is often disputed. Even if you neck size, eventually you will need to full length size. Perhaps every 2-4 firings as the case will become to tight in the chamber. Neck sizing is only relative to rifle.

 

[condor bravo]

For initial trimming, load and fire any new or once fired used rifle brass in your rifle one time to take into account the initial stretching. Then trim to recommended length. Deburring inside and outside case mouths will be separate operations. Chamfering implies cutting a bevel inside the case mouth to aide bullet seating. However this results in thinning of the case mouth or taken to the point of a knife edge ridge at the mouth. I do not recommend doing that and case flaring is usually not needed for jacketed. However flaring the case mouth is required for cast bullets and this is done with a Lyman M die.

Most do not bother trimming handgun brass.

 

[Sure Shot Mc Gee]

After a trim. Its quite noticeable observing the neck mouth showing a flared excess of material over both inside & outside edges. I try not to chamfer inside the neck. I'm a believer in letting the dies spindle/ expander do the smoothing of that little bit of flared brass. Otherwise the bullets seating surely will.

 

[Unclenick]

Fariaguard,

The Wilson is a flat cutting trimmer. Chamfering and deburring are second operations. Wilson makes a combination chamfering and deburring tool that is required for deburring. If you want more carefully uniform chamfers, they make both 45° and a 30° chamfer tools that you use in place of the trim cutter. Contrary to the description of the 45° cutter, it is the general purpose chamfer tool for flat base bullets and general bullets. The 30° chamfer was developed for long shallow angle boat tails as are commonly on VLD bullet shapes, but I like the shallower angle for all boat tail bullets.

 

[T. O'Heir]

$170.00, yikes! No trimmer chamfers and deburrs. Chamfering a bottle necked case takes the place of the flare put on a handgun case. Cutting any metal will produce a burr. Needs to come off. Rocket science it ain't though. One light turn with a deburring tool and you're done. One time thing until you need to trim.
"...When do I need to trim my brass..." You need to check case lengths every time, but you only trim when the case gets longer than the max case length given in your manual. BNIB brass(and once fired out of another rifle) needs to be checked for length, FL resized and chamfered and deburred. New brass is not ready to load out of the factory.
Handgun cases rarely need trimming. Handgun cases rarely stretch. They do need checking(for cracked mouths mostly) every time but usually they don't need anything else.
"...reading about full length, shoulder and neck resizing..." It's full length or neck. There's no shoulder sizing. However, FL usually pushes the shoulders back a bit. There's really no measuring how much though. As long as the FL sizer die is set up properly it'll be fine.
Neck sizing can only be done with brass fired out of one rifle. And only for bolt actions. Semi-autos, levers and pumps require FL every time.

 

[highrolls]

fariaguard, I have one of these, actually got the one that has the mini table top mount with slots for extra case holders.

Here is the great part about it, what Unclenick said. Due to the holder design this thing makes a perfect 90 degree flat cut every time. I store it with an RCBS hand-champfer/deburr tool which in my opinion is far faster and easier than adding another hand crank for the trimmer.

Operationally, there are a few necessities. First, you gotta zero the micrometer to get the advertised accuracy. The way you do that is one of those "which came first, the chicken or the egg" things. To zero the micrometer means to use a perfectly pre-length case which all your future measurements will reference. So I also store these reference cases with the trimmer, one for each caliber. Note that you may end up with multiple cases holders as well, one for each caliber.

The downside is to eventually buy the Carbide Cutter Upgrade. In my opinion, not a choice but a necessity. The steel cutter that is supplied with the unit looses its cutting edge after not very many cases. I resharpened it with a small grinding bit and got a few more cases trimmed, changed to the carbide cutter and am still going well. In my instance, around 500 223 and about the same number of 30-30 took the edge right off the supplied cutter. I do not use the power drill mod, still just hand cranking.

 

[Unclenick]

…No trimmer chamfers and deburrs

You haven't been keeping up with the times. There are four I am aware of: The Giraud and Gracey and Power Trim II, and RCBS makes one for their Trim Pro tool. They are called 3-way cutters or Tri-Cutters. Here's a link to the RCBS style, which is a piloted 3-blade cutter. The Giraud cutter uses lathe tool inserts specially ground so the case mouth is trimmed by a notch in the cutter, and the sides of that notch are angled to handle the chamfering and deburring.

 

[turtlehead]

I ordered the Giraud Tri-Way trimmer in .223. Will be here this week. It gets great reviews.

 

[Unclenick]

The Giraud is fast. I like mine a lot, despite the price. One thing you will find that differs from the RCBS piloted method is the case shoulder registration (vs. pilot on the RCBS) used by most three-way trimmers, including the Giraud, will cut an eccentric chamfer in case mouths with uneven neck walls or in cases whose necks have been pulled off-axis by the expander ball during resizing. Some don't like this, but I find it a useful for visual quick sorting of cases for practice from cases for top precision. The RCBS cutter, because of the pilot, will keep the chamfer centered, regardless, but the deburring will be deeper on the thicker side of a non-uniform neck wall.

 

[cw308]

fariaguard
What rifle are you reloading for?
Bolt actions, sizing brass with .001headspace ( bolt face to datum ) using the RCBS Precision Mic makes sizing easy. Measure your fired case, clean your brass, set up your F/L die to touch the shell holder, back out die one full turn. Size your clean fired brass & check the size against the measurement of the unsized fired brass. Then either screw the die down or up until you get the proper headspace. Measure the OAL length of the sized case to get proper trim length. I like the trim back .002 from max. If your goal is accuracy each case should be the same. Redding precision seating die is something to look at. Full length sizing & seating with the Redding seating die, your runout will average .001. Hope I helped.

 

[1100 tac]

Thank you Uncle Nick, saved me a bunch of typing.