[rexti]

I am brand new to the reloading scene. If this question has been posted and I missed it somewhere just point me in the right direction.

I purchased the RCBS Rockchukker Supreme Master reloading kit. While reloading my 9mm, I had no problems (straight case). However when I started with the .270 WSM, I ran into a question about the Case Overall Length (COL). I purchased new Winchester .270 WSM cases and ran up a few dummy loads (no primer or powder) for practice. I immediately found out that on measuring the COL with calipers, the lengths varied by .001" - .004". I made sure the die was locked in to prevent slippage. I then measured the case lengths without the bullet and found the same variance in the blank cases. My concerns are: 1) Do all new cases vary in lengths like this right out of the bag?, 2) Are these differences significant?, 3) Should I be trimming "new" cases to exact lengths?

Thank you for helping a "newbie" to reloading

 

[Lane]

1) Do all new cases vary in lengths like this right out of the bag?, Yes

2) Are these differences significant?, No, not really.

3) Should I be trimming "new" cases to exact lengths?

Can if ya want. many folks find the shortest case--with in specs-- and trim the rest to that one. Or just trim to book length on all, and the short ones will catch-up in length after a few firings

 

[rexti]

Thanks, Lane. You helped remove some of my initial frustration. I am a stickler for accuracy and didn't want to screw up my new Browning BLR .270 WSM.

 

[Lane]

Your welcome!

The more ya do this, the more detailed you'll get

I kind got to this stage so far:

1. examine cases for defects
2. de-bur the primer pockets inside case
3. Full length resize all of them
4. trim all to the shortest usable case length
5. weigh all cases, and seperate into groups
6. Chamfer/ream inside/outside case mouth
7. Prime all with hand-prime tool
8. Ready to charge and seat the bullets

All my bullets are moly coated.

but there are so many other gadgets out there to "Assist, and empty your wallet" in the reloading process

 

[rexti]

Thanks for the details.

Moly coated??? Please educate me.

 

[bsn]

Factory brass can vary quite a bit, I always trim and debur before I use it the first trime. The Lee case trimmers are very inexpensive and foolproof I would suggest getting one.

 

[rexti]

Thanks, now that I have loaded a few 9MM and a few .270 WSM, I see that will need a couple more pieces of equipment: a bullet puller, case trimmer, and a charge trickler.

Also, is it normal to see a a small amount of copper shavings at the neck of the case after seating a bullet (I loaded a few Nosler E-Tips this afternoon and that is what I saw. A quick fingernail around the top of the neck took care of the problem.

 

[gunchamp]

Deburring the cases should help with the copper shavings. I alaways trim new brass to size then debur.

 

[Lane]

Thanks for the details.

Moly coated??? Please educate me.

Before we type our fingers till they are sore, check out all these cool Free reloading videos--on line at AmmoSmith :

http://www.ammosmith.com/ammosmith-com-video-library.php

These will really help you out!!

Edit: Your signature has been deleted. No advertising without the approval of the board owner.



Moly coating is a first generation dry bullet lubrication process. It reduces barrel pressures and reduces copper fowling. The newer and probably better coatings are: Boron Nitride and Tungsten Disulphide
http://www.6mmbr.com/bulletcoating.html
http://6mmbr.websitetoolbox.com/post?id=2927448


This will help ya a lot

 

[rexti]

Thanks to Everyone for Your Comments

Now it's time to digest all the information you have given me.

 

[broom_jm]

Rexti,

A few important things to realize about bottle-necked cases:

1) They headspace on the shoulder, so if the case neck length varies slightly, it is of little consequence, unless you're applying a crimp. That's not typical for the 270WSM, except in a semi-auto or lever gun.

2) If the longest case you have can be easily chambered in your gun then the neck is not too long to be used. If you try to chamber said case and you feel some resistance, the case mouth may be hitting the end of the chamber...that isn't very likely with the differences you mentioned.

3) Presuming none of your cases are too long, the bullets will be projecting into the throat of the rifle and will be engaging the rifling long before they have exited the case mouth. With this in mind, those slight variances of .001" - .003" in OAL might affect accuracy, but IME, it won't be significant.

4) It is smart to size brand-new cases, but unless you find extreme variances in length, it is rarely necessary to trim them. (Unless the new cases fail to chamber easily, I will typically just use the sizing die to make the case mouth round and uniform.) I still recommend that you chamfer/deburr, as that will aid in seating bullets and make the loads more consistent.

Long story, short: Minor differences in case length or cartridge OAL are not a big deal, for hunting loads. If you're into benchrest accuracy, then yes, you need to pay attention to those tiniest of details. After as few as 2 or 3 firings, you will find that some of your brass is getting too long; trimming all of them to a uniform length is indicated, at that time.

 

[rexti]

Lever Action .270 WSM

Broom,

Thanks, this is quite helpful.http://shootersforum.com/images/smilies/smile.gif

In your notes you said:

Rexti,
1) They headspace on the shoulder, so if the case neck length varies slightly, it is of little consequence, unless you're applying a crimp. That's not typical for the 270WSM, except in a semi-auto or lever gun.

I am loading for a Browning BLR (Lever Action) .270 WSM. Is this what you mean when you say "lever gun"? If so, what precautions do I have to take? I am still a bit confused about the "crimping" process. Do all cases have to be crimped for a lever action, or just those whose bullet has canulars?

 

[ForneyRider]

I load 270 WSM for Win mdl 70.

I use 130gr Accubond loaded to factory Winchester 130gr Ballistic Tip factory ammo length and velocity.

I use Norma brass, CCI 250 primer, IMR 4350 powder, and the afformentioned bullet. I tried R19 and R22 as well, but the IMR 4350 worked best for my combo.

Your lever gun has a bottom feed mag, and not a tube. I roll crimp tube fed ammo (30-30) and revolver (38/357,41,44 Mag) ammo to keep the bullet from moving around. I taper crimp 45 ACP as it fed better in my pistols than when I didn't.

Above answers to case lengths I agree with. If you buy new Norma or Nosler brass, it is ready to go out of the box. Fed, Rem, Win and Hornady will need to be prepped some. Usually the mouths are dented on the cheaper brass.

I like the Lee trimmer as well, but use the Redding trimmer lathe when I need to do custom stuff, like 30-30 for the Hornady FTX lever bullets that suggest I trim to shorter than standard length. Trimming with Lee in a cordless drill is pretty fast. I use the zip trim, and hand trim and you can get worn out pretty quick on big jobs.

 

[rexti]

I am down to two choices for my .270 WSM loads:

1) Barnes TTSX 130 grain, 61.5 grains of R19, COL 2.090", MV 3100 fps - Gives me 1.35" 3-shot group at 100 yards
2) Hornady GMX 130 grain, 58 grains of H4831, COL 2.785", MV 3100 fps - Gives me 1.25" 3-shot group at 100 yards

I think I will stick with the GMX to help reduce copper fouling in my new rifle.