New brass vs once-fire - A big difference?

[Newkid]

I am off to a reloading meeting on Thursday and might not have fired cases washed, sized etc. ready for Thursday. I could load up some new cases and take them along to get started?

Would it make that much difference? Can anyone point me in the direction of a comparison article?

Many thanks

Peter

 

[Tozguy]

Not sure about what you mean but this article might be a good 'primer' for you.
Good luck and have fun.
http://riflemansjournal.blogspot.ca/2010/06/basics-resizing-case-dimension-changes.html

 

[watercam]

I would have said 'Not too much' difference until this last weekend. The gentleman I was scoring for was fire forming .284 rounds in a Barnard action and had not run them through a sizing die. His opinion was that it could potentially ruin unfired brass - never said how and we never got around to discussing it. In any event, it was new Winchester brass and the head space was very erratic. A few were so long he simply could not close the bolt.
He did win the match though so there is the real answer!

 

[Newkid]

Perhaps it would be a good idea to run them through full length resizing just in case?

Thanks for the info - especially the link!

Peter

 

[itchyTF]

You might want to double check the length also, just in case.

 

[hogan]

Really looking to know what your brass is doing?

A Wilson Case Gauge & caliper, or an RCBS Precision Mic will give you dimension of virgin brass and dimension it stretches to once it has been fire-formed.

Worthwhile to test new brass to verify it will chamber in your rifle, especially if you have a custom built or accuracy rifle. If you have some brass that chambers and some that doesn't, need to FL size the brass that won't chamber to point where bolt will just close with mild resistance. When you have fired brass from your rifle, it should chamber easily. Eventually, may have to trim your brass to a uniform trim-to length and you will know case necks are too long when FL sized brass will not close. Usually 5 or more firings before cases need trimming. Some will trim cases to uniform length with new or 1x brass.

If you own none of your own gear and are going to learn from or use a friend's gear, bring new cases or only fired cases that you know came from your rifle...

 

[Newkid]

Thanks to Hogan and others for the responses.

I sorted my time issue but what I am finding is that once fired lapua 308, after resizing is not chanmbering or very tight. I am now resizing to 1.620 (0.4 neck length) to make sure rounds chanmber correctly. Bullet ogive is fine and not giving me any problem as I have lots of clearance, but my Rem700 308 (which has fired all the brass) will not let me go beyond ca1.624". am I correct or is there something I am missing when resizing?

Thanks in advance.

Peter

 

[jcampbellsmith]

Peter. I loaded 50 new Nosler cases the other day from my 260 Rem. All I did with these cases was tip them out of the box, run an expander mandrel through them and then ultrasonic clean them. I don't seem to use the same load for first off firing as I do once the brass has been fired in my rifle. However I don't have a enough data to give a good opinion on what my loads for an accurate first firing should be. I seem to muddle by with my first firing of the brass. Regards JCS

 

[BoydAllen]

IMO the importance of the difference between unfired new brass, and once fired, is closely related to the potential of the rifle, and the quality of the shooting setup. For an accurate rifle, well supported, shot by someone who has some skill, once fired will generally show better results. Tell us about what you are using your loads for, and what your best and average accuracy results are.

 

[Newkid]

Hi Guys

I use my 308 mainly for stalking (and I am often grubbing around trying to find my lovely lapua brass in the bog!). The Rem 700 SS rifle shoots 150gn Vmax to less than 1MOA with 43.3gn of N140, up to 200yds.

The accuracy is fine and even tight brass does not vary too much. My main concern is whether my reloading technique is missing a fundemental parameter which means I am not sizing correctly. John has suggested I size without the necking in case this is restretching cases, and is one of the tasks on my lsit of TBDs.

Cheers

Peter

 

[amlevin]

The Rem 700 SS rifle shoots 150gn Vmax to less than 1MOA with 43.3gn of N140, up to 200yds.

How much less than 1 MOA? Mine has shot as well as .2 MOA when I did my part on a windless day.


Funny how the number "43" seems to show up a lot when working up loads for this rifle. The absolute best load for mine has, over the last 4 years, been 43.5 grains of Varget and a 175 gr Nos C/C. Next is 43.8 gr of Varget with a 168 Nos C/C.

T

 

[Newkid]

Thats interesting - .2! I can get down to 0.5MOA on a good day, but would need to do a bit more development to go further.

I am going to a longer barrelled CZ550 for paper bashing (26") with the hope of FT/R in future.

Cheers

Peter

 

[amlevin]

Thats interesting - .2! I can get down to 0.5MOA on a good day, but would need to do a bit more development to go further.

I am going to a longer barrelled CZ550 for paper bashing (26") with the hope of FT/R in future.

Cheers

Peter

It was actually a little better than .2 for a "personal best" with this rifle. Here is a 5 round group that measured .191" C-C.

 

[BoydAllen]

Just out of curiosity, what is the diameter of the circle, and what is the spacing of the lines that make up the grid?

 

[DougMH]

I am off to a reloading meeting on Thursday and might not have fired cases washed, sized etc. ready for Thursday. I could load up some new cases and take them along to get started?

Would it make that much difference? Can anyone point me in the direction of a comparison article?

Many thanks

Peter

Frankly, with Lapua brass, I've noticed NO difference

 

[amlevin]

Just out of curiosity, what is the diameter of the circle, and what is the spacing of the lines that make up the grid?

This target was printed from a download. Never bothered to measure the circle but the grid lines are just under 1/10". The printer reduced the target from original. I only wanted it for the "X" and used a caliper to measure outside to outside of the "grease marks" and then subtracted .308", thus the "net" of .191"

 

[spclark]

I've found virtually no difference in accuracy or performance between new and fired factory (Norma) brass in 6XC. Essentially the same with 'made-up' brass for 6HAGAR too; first firing's a 'fire-form' & at 600 yards it shoots as good as fired cases if I do my part.

Understand I shoot sling & irons (mostly) so I score by the rings, not with a micrometer so benchresters' experiences may be different.