Case length

[Twotone]

Hi all,
Another newbie question so sorry if its daft. Having used factory once fired brass they are nearly all around 1.29" and I then trim to 1.28". Oal when finished has vpbeen 1.58". I have used these measurements religously when loading my cases. I recently bought a load of new brass from Starline that is way under those sizes. Do I now have to adjust my loads and OAL accordingly? They are between 1.280 and 1.283". Am I just being too anal ? Does.007" make a difference to my powder load?

[Ojaileveraction]

What caliber?
New brass many times needs to be trimmed to size chamfered inside and out the deburred.

With that said. As I understand, trimming brass to a uniform length helps in getting a uniform crimp. I think anywhere between the max and the min length would work as long as all the brass is the same.

Changing powder weight due to brass length probably not a good idea.

[JEBar]

can't speak for anyone else but I don't worry about 7 thousandths .... I did randomly measure the first couple of batches of cases I ordered from Starline but since then I open the box and load them .... after they have been fired a couple of times I do measure and trim as necessary

[BigAl52]

You can trim them if you want but I dont. I hate trimming cases. The only reason to trim cases in a pistol caliber is to have them all seating at the same depth when seating bullets to the crimp groove. If your within 2 or 3 thousands its not going to make much difference. 10 thousands and beyond will show some. But I usually cull out the shorter cases and load them together. Al

[CT_Shooter]

I do trim the brass (that I have been given in packages of mixed headstamps) in order to give them a consistent length. However, almost all of my .357 and .38 spl brass came from factory ammo that I purchased when I first started shooting. That brass is stored in boxes of fifty just as they came from the factory and I do not trim them, since they are already the same length.

I handle the brass this way to guarantee consistent bullet seating and crimping from box to box; and I always adjust the seating die and the FCD die for each individual box that I process.

[Squatch]

I buy the caliber specific little Lee hand held case trimmers. Just bought one for 44 specials! I do everything one at a time so it's no big deal to use this to check each case. New brass tends to grow a little the 1st few times it's shot. Then it usually settles down and doesn't really need much trimming.

For me it's about getting a consistent crimp.

[Rugerfanboy]

Hi all,
Another newbie question so sorry if its daft. Having used factory once fired brass they are nearly all around 1.29" and I then trim to 1.28". Oal when finished has vpbeen 1.58". I have used these measurements religously when loading my cases. I recently bought a load of new brass from Starline that is way under those sizes. Do I now have to adjust my loads and OAL accordingly? They are between 1.280 and 1.283". Am I just being too anal ? Does.007" make a difference to my powder load?

.007" will make no difference in my opinion....but it "will" effect your crimp thou. All you'll have to do is, readjust your crimp die. No need in adjusting the OAL and the load. But, you have to remember also, those Starline cartridge cases are brand new and they will grow a few thousands during the first shooting. I would just load them up and shoot them. But, if it does bother you, you could always just send them to me and I'll just use them in my Ruger revolvers and my Henry Big Boy chambered in 357 Magnum.

For me it's about getting a consistent crimp.

Consistent crimp is paramount in my option. I always work up my load data cause I'm after a particular velocity and cartridge case pressure. The internal cartridge case pressure deals with a cartridge case sealing inside of the cylinder. It takes a certain amount of pressure to achieve this....so it's one of my key points that I'm after. If the cartridge case does not seal inside of the cylinder, you always take a chance of blow back. Meaning unburnt powder and gases could come back and hit the shooter in the face. This could even happen in semi-auto pistols as well. I have two reloaders that I shoot with from time to time and one of them never works up his load data. His wife will not shoot his reloads cause she always gets hit in the face with unburnt power. I've even seen him flinch before from being hit himself. He won't emit it cause all he cares about is putting lead down range. And he always wonders why me and our other reloader friend can out shoot him. Consistent crimp also helps "a little" with a lower standard deviation and a lower velocity spread between shots....which in turn....meaning my reloads are more accurate. I hate reloads that have accuracy issues...!!!