High Neck Tension ? Weld

[MGS]

Nov last year loaded 6BR for short range (up to 600yds) Ballinger belt comp. Due to gun problem did not get to fire them, and it was in fact April this year before I got the chance.

Blew 9 of 14 primers. Apart from everything else, it sort of b.......s your confidence in things, which dont help competition results. Anyway, I have since come across a couple of articles which suggest that there may be some "neck welding" going on when loaded rounds are left unfired for some time. After reading the articles, went to range & shot over chrono. Well no ruddy wonder they were blowing. Had gained another 200fps ( going up to av of 3160 with 105SMK) on what was already a fairly hot load, but one well withing safety as established by previous tests.

My question is this.

Has anyone any idea of how long rounds can be left before this happens?

Load is 32.5gn 2208 in Lapua over WSR.

[a.JR]

MGS, The main problem with the bullet sticking in the neck comes from i believe the powder residue, the problem is worse in a high humidity enviroment.. The secondary problem is that it is not consistant ,cartridge to cartridge.. I have a time limit of 6 hours from load to shoot ,after that one or two of the 42 rounds i load will do exactly like you say ,they will increase in pressure and for me that is not an option..JR..Jeff Rogers................ [quote="MGS"]Nov last year loaded 6BR for short range (up to 600yds) Ballinger belt comp. Due to gun problem did not get to fire them, and it was in fact April this year before I got the chance.

Blew 9 of 14 primers. Apart from everything else, it sort of b.......s your confidence in things, which dont help competition results. Anyway, I have since come across a couple of articles which suggest that there may be some "neck welding" going on when loaded rounds are left unfired for some time. After reading the articles, went to range & shot over chrono. Well no ruddy wonder they were blowing. Had gained another 200fps ( going up to av of 3160 with 105SMK) on what was already a fairly hot load, but one well withing safety as established by previous tests.

My question is this.

Has anyone any idea of how long rounds can be left before this happens?

Load is 32.5gn 2208 in Lapua over WSR.[/quote]

[Woody_rod]

AHA!!

So I am not going mad....well, not just yet. I thought I was imagining this myself, now I know it has a name: "neck weld".

[BATattack]

heres a question . . . . did you use fired brass to do your load development and were you shooting new brass at your match?

[Razer]

My question is this.
Has anyone any idea of how long rounds can be left before this happens?

There is no answer to this as we would need to know your exact loading procedure. However we can draw some comparisons. Factory loads,including ex-military loads can be over 30years old, and if stored correctly, will be perfectly OK. I have hot hand loads in several calibres that were loaded over 13 years ago and are still perfectly safe with no changes in velocity or chamber pressure. They also have been stored correctly so there is no moisture to create corrosion.
With hand loads cleanliness is vital for maintaining the long term integrity of your cartridge. I tumble all my brass after firing and store it in those plastic peanut butter jars which keeps the case from attracting moisture. I neck size which avoids "any" lubrication inside the neck. If I need to full re size, I tumble the brass again to remove case lube,[there are other methods such as ultrasonic,etc.]. When I seat the projectile I make sure that I don't have sweaty fingers. The aim is to seat a clean projectile into a clean neck. This should give you similar results to factory loads[or new brass/projectile].
What you are getting is most likely a chemical reaction created from case lube/moisture between brass and projectile which is "bonding" the two together.This is not affecting recently loaded cartridges, but, will affect your loads after a period of time,again, depending on how it is stored.
My son shot a 99-11 in TR last week using up some old BJD's that were loaded 2 years ago, with no pressure signs at all.
Many years ago we used to dip the base of projectiles in varnish before seating for reasons no longer applicable now. There was never an issue with this as it created a film that did actually bond,but it also prevented the case/projectile touching[and reacting] and so gave consistent neck tension.
My definition of welding is, loosely, the "homogeneous joining of two metals". I don't think you would want that??? A bonding, caused by chemical reaction, caused by loading practices, would be my humble opinion.
Ray.
PS: to gain 200fps would take an extreme difference in neck tension but I will stand corrected.There are "other factors" though which will create this.

[Cameron Mc]

Nov last year loaded 6BR
Blew 9 of 14 primers. gained another 200fps ( going up to av of 3160 with 105SMK) on what was already a fairly hot load, but one well withing safety as established by previous tests.

My question is this.

Has anyone any idea of how long rounds can be left before this happens?

Load is 32.5gn 2208 in Lapua over WSR.

Anyone else use a load around this mark. Would be way too hot in my rifles.

Cameron

[MGS]

Thanks for the replies.

New brass was initially used for load development, but reloaded at range to determine final load.
"What you are getting is most likely a chemical reaction created from case lube/moisture between brass and projectile which is "bonding" the two together.This is not affecting recently loaded cartridges, but, will affect your loads after a period of time,again, depending on how it is stored. "
This is at least to me ,the probable answer, and to avoid a repeat, I will wherever possible, load closer to the actual shoot. Or can anyone suggest a suitable case cleaning method (such as ultrsonic) so loads could be prepped in advance?

Thanks again

Maurice

Meant to add - Loaded batch of rounds with the load noted above 32.5 2208 etc but using 105 AMax for some bunny busting. Not only was there no problem with pressure etc, but AMax did a mean job at (lasered) 210 - 428 yds

[M12LRPV]

I've been on a mission over the last few weeks to eliminate this as a cause of flyers from my own ammunition.

I found that not only will brass that's loaded tighten up randomly but brass that's sized and left will too so brass that's been sitting unused for a while gets run through and expander die before loading.

Also adding to what a.JR said about the 6 hours. If I can't load the night before i'll load earlier and seat the bullets high then on the morning of the shoot just bump them down to their final seating depth. Any which feel "wrong" in that final bump get moved to the end.

Together all of this seems to have done the trick. For the first time ever last weekend I shot without 4 ring fliers.

Now if I could only deal with the clean barrel 3rd shot jump i'd be right

[MGS]

Just a follow-up to the earlier comments. Shot ammo loaded 12 days ago , but with 1 full grain less powder - 31.5, instead of 32.5.

At 500 yards trajectory was practically identical. 7 MoA, my usual setting put me right in the bull. Windage needed a little more adjustment than expected, but hardly any cause for comment.

I guess this just reinforces my decision to load long and reseat as close to match as possible.

Maurice

[BATattack]

yes loading long and seating back is a common practice. after similar problems this has been my routine and has worked well

[CEW]

"Now if I could only deal with the clean barrel 3rd shot jump i'd be right"


This problem can be solved by loading those first two sighters shot on a cold clean barrel with another half a grain of powder. I have heard that there is a number of Fly shooters that have done this for years also.
With my 6BR I load 31.5 grains of 2208 in the first shot, then 31.0 for the second then the rest are 30.5, or my usual load. Be sure to mark them though . With this method I get a first shot V elevation right back to 900 M. This works for me, but you will need to trial it in your own cartridge.

Peter D.

[M12LRPV]

This problem can be solved by loading those first two sighters shot on a cold clean barrel with another half a grain of powder. I have heard that there is a number of Fly shooters that have done this for years also.
With my 6BR I load 31.5 grains of 2208 in the first shot, then 31.0 for the second then the rest are 30.5, or my usual load. Be sure to mark them though . With this method I get a first shot V elevation right back to 900 M. This works for me, but you will need to trial it in your own cartridge.

Peter D.

In a 223 with 2208 i'm already running compressed loads. There's no room for any more

I recon my real improvement will come by ditching the factory barrel and buying a good target barrel.

[taka]

M12

why not use 2206h?
then you would have room for the extra powder in your 223.

Steve

[M12LRPV]

M12

why not use 2206h?
then you would have room for the extra powder in your 223.

Steve

It's an option but I like how 2208 performs plus I use 2208 for 303's so i'm just buying a single powder for both.

Then again with 2208 disappearing at the moment a move to 2206H may happen by force.

[bruce talty]

Nov last year loaded 6BR for short range (up to 600yds) Ballinger belt comp. Due to gun problem did not get to fire them, and it was in fact April this year before I got the chance.

Blew 9 of 14 primers. Apart from everything else, it sort of b.......s your confidence in things, which dont help competition results. Anyway, I have since come across a couple of articles which suggest that there may be some "neck welding" going on when loaded rounds are left unfired for some time. After reading the articles, went to range & shot over chrono. Well no ruddy wonder they were blowing. Had gained another 200fps ( going up to av of 3160 with 105SMK) on what was already a fairly hot load, but one well withing safety as established by previous tests.

My question is this.

Has anyone any idea of how long rounds can be left before this happens?

Load is 32.5gn 2208 in Lapua over WSR.

Hi,I don't get that problem i coat my bullets with WS2and have had some .308s loads for a couple of years they fired OK.Bruce