6.5x55 sooty cases N160 very late follow up

[charlieboy-shooter]

Hi Guys,

I posted way back prior to the 1st lock down regarding very sooty cases with N160 with 120 gr Pro-hunters #1720 in new but old shop stock Norma cases. All load regardless of charge 1/2 crimped. Col between 3.00 and 3.03
Due to the differing load data being so varied and warning not to relying on advice offered on Quickload for N160. I started with the lower published data which fitted in the other threads regarding N160. ( 43.8 a 45.7gr)

Well I just produced soot,soot and more soot. ( used CCI and Sellier Bellot primers with same result) So I followed some advice from here and in keeping with the Lee modern reloading manual stating max load of 50.7gr. I worked my way up toward this to see if the sooting stopped. At 48.9 gr had 1 clean case and 2 sooty. I got 3 clean cases at 49.4grs see attached photo ( hopefully). The accuracy of the last few sooty loads and last was very good but the felt recoil went up noticeably ( maybe just my perception after firing numerous loads) the bolt was not stiff and looking at the cases I don't think they look like a hot load. However I have not progressed anymore as wondering.

1) looking at old threads so many stated they had good results around mid 45grs. Any suggestion why my results differ so much ?
2) wonder if 49.4gr will cause excessive meat damage ( I know there's one way to find by testing). I don't have a chronograph and don't think it's on my Xmas list.

As a addition when I have used the kinetic hammer to unload some of the cartridges I found the bullet dislodges relatively easily, same in a test with a loaded Federal case.. using Lee pacesetter die set.

So before I going ahead and re zeroing the rifle and see I'd just thought I'd ask you guys for your views please.

Thanks

 

[Woodsmoke]

new but old shop stock Norma cases.

They might possibly benefit from re-annealing . . . . .

 

[Stevie/P]

I load 49grn N160 with 120grn pro hunter I'm getting 2940 confirmed chronograph. Stupid accurate out of a 24" barrel.as for sooty cases none with neck size cases I've seated them 30 thou deeper than Sierra suggest at 3" oal works for me although this combo is a little harsh on small size deer.

 

[Foxyboy43]

I shoot 120 prohunters over only 45gns N140 - lovely soft load but still highly effective and you see the strike clearly in the scope. Recently experimenting with same load and 130 Sierra Gamechangers - very accurate and again soft to shoot but still plenty of poke! If they dislodge easily are you noticing that they seat without any real effort? In any case (!) you should also recheck your die settings - every batch I do I a percentage check for tightness by firmly pushing the tip into a small hole drilled in my bench before I crimp - this will catch any loose rounds. Good luck

 

[Leupsak]

I had a similar issue until i bought new brass

 

[ashray]

have you tried using a lee factory crimp die? i use one on all my 6.5x55 .

 

[Foxyboy43]

Me too!!!

 

[SCC]

Having worked up loads of n160 with 120, 129, 140, 143gn heads I’ve encountered a fair bit of soot along the way. I came to the conclusion that although some loads were fine with n160, a lot were prone to sooting.
This was exclusively with std CCI primers BTW ....i also lightly crimp all my loads (Lee factory crimp).
I have since moved over to n550 and RS60 and now have zero soot and better MV vs load.
For my desired MV and rifle (85 finnlight 6.5x55) the faster powders work just great.
Just my particular observation.

ATB
SCC

 

[Barkingsnake]

Hi Guys,
...

So before I going ahead and re zeroing the rifle and see I'd just thought I'd ask you guys for your views please.

Thanks

What sort of ambient temperature was it when you tested? I've had mixed "smoking" results with N160 but always good accuracy and I have defaulted to my staple Remington Magnum primers with it to no avail but...
I anneal the lot after firing...didn't help but I've no evidence that hard necks helped or hindered either.
Case neck tension?
Overall length looks the same as mine...

I suspect it's a bit too slow for 120grain as 129SST works superbly and doesn't smoke at the loading I use.

I think 50.7grains is a bit too much but it's just an opinion.

 

[charlieboy-shooter]

Thanks for the replies guys.

Foxboy, I'm Using the normal lee die pacesetter die set, set as instructions in press so no adjustment like a collet die and I am using the Lee factory crimp from the set to crimp as 'ashray' suggestion as I do on all my loads. The bullets do not easily move in the case certainly not by hand, just with the kinetic hammer. 3 or 4 good taps against a hide/copper mallet.
Regarding new brass, I have considered trying different cases, as I now have once fired Federal cases but found on a single test load the neck tension seems to be similar to the Norma, hence wonder if the issue, if it is neck tension, is related to the die and expander ??

SCC, I have certainly previously read that N160 can be sooty especially on frosty mornings.
I have tried to get some Swiss Powders but none locally that I can find. I was thinking of RS62 only as despite RS60 being listed as a single base it clearly isn't. but can't get either ayway.

Barkingsnake, Regarding temperatures it certainly hasn't been the extremes i.e. frosty mornings or high summer temps but certainly normal summer temps and have fired test loads in march but equally that could be fairly mild I guess don't remember. I had wondered if Magnum primers could help so interesting to hear it made no difference.

 

[Foxyboy43]

One final thought - if neck sizing - can you feel resistance then further movement needs a bit more effort as you reach the end of your press handle travel? If not the die defo needs adjustment - beyond that I am beat!

 

[charlieboy-shooter]

One final thought - if neck sizing - can you feel resistance then further movement needs a bit more effort as you reach the end of your press handle travel? If not the die defo needs adjustment - beyond that I am beat!

Full length resized all the new cases.. hence no adjustment. The 6.5 is the only calibre I have which I do not have a Collet die for.

 

[Sharpie]

To get a rough idea of neck tension, take resized cases and measure outside neck diameter. Callipers are just about up to this but a micrometer is better.

Then finish reloading them and measure again. The neck diameter will have increased as the bullet is forced in. 1/1000" would be the bare minimum. 2 or 3 better, for hunting ammo imo.

For the slower powders such as the one you are using, pressure has to build up to get it burning properly before the bullet is released from the neck, either by overcoming neck tension, or maybe also a crimp, though I think that is usually a poor substitute for decent neck tension. A hotter primer might help, but they also have negatives, such as popping the bullet out of the neck before the powder has had a chance to get burning properly, a hot primer won't necessarily make that happen any faster or more completely.

When working properly the neck should expand, obturate and seal the chamber. A bit of soot on the neck is not unexpected, normal, but getting soot all down the case is not normal. The neck has not obturated and sealed. Which is bad for the rifle, that soot is deposited from gases escaping the chamber and exiting elsewhere instead of down the barrel as intended.

It may be as simple as that the brass at the neck, is too hard/springy perhaps due time age hardening process, though I've not heard of that before. If so, maybe an annealing might fix that.

Or perhaps you simply have a very sloppy chamber, particularly in the neck. You could measure a fired case to get an idea of what they get blown out to, and whether this is reasonable having established the maximum allowable dimension from SAAMI or CIP dimensions.

 

[borbal]

Or perhaps you simply have a very sloppy chamber, particularly in the neck. You could measure a fired case to get an idea of what they get blown out to, and whether this is reasonable having established the maximum allowable dimension from SAAMI or CIP dimensions.

Interestingly, while SAAMI have a maximum dimension on chambers (usually +0.002 on stated minimum diameters), CIP do not state a maximum on their chamber diameters. The reasoning goes that with regards to safety, the bigger the chamber is, the better.

 

[jonnah]

There was a thread on this forum a couple of years ago ,where a member was experiencing the same problem using N160. To overcome this problem a member recommended using Remington 9.5 primers has these have a higher brisance (hotness).Hope this helps.




























































































































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[charlieboy-shooter]

To get a rough idea of neck tension, take resized cases and measure outside neck diameter. Callipers are just about up to this but a micrometer is better.

Then finish reloading them and measure again. The neck diameter will have increased as the bullet is forced in. 1/1000" would be the bare minimum. 2 or 3 better, for hunting ammo imo.

For the slower powders such as the one you are using, pressure has to build up to get it burning properly before the bullet is released from the neck, either by overcoming neck tension, or maybe also a crimp, though I think that is usually a poor substitute for decent neck tension. A hotter primer might help, but they also have negatives, such as popping the bullet out of the neck before the powder has had a chance to get burning properly, a hot primer won't necessarily make that happen any faster or more completely.

When working properly the neck should expand, obturate and seal the chamber. A bit of soot on the neck is not unexpected, normal, but getting soot all down the case is not normal. The neck has not obturated and sealed. Which is bad for the rifle, that soot is deposited from gases escaping the chamber and exiting elsewhere instead of down the barrel as intended.

It may be as simple as that the brass at the neck, is too hard/springy perhaps due time age hardening process, though I've not heard of that before. If so, maybe an annealing might fix that.

Or perhaps you simply have a very sloppy chamber, particularly in the neck. You could measure a fired case to get an idea of what they get blown out to, and whether this is reasonable having established the maximum allowable dimension from SAAMI or CIP dimensions.

I have a micrometer so I will do that. I will measure cases and loaded cartridge and see.
I will equally measure fired cases to get a gauge on the chamber as well. However have fired factory loaded Federal and Privvi and had good seal with no soot.
Thanks.

 

[Border]

Seating the bullet deeper may also help against the sooting issues.

 

[NP435]

I shoot 120 prohunters over only 45gns N140 - lovely soft load but still highly effective and you see the strike clearly in the scope. Recently experimenting with same load and 130 Sierra Gamechangers - very accurate and again soft to shoot but still plenty of poke! If they dislodge easily are you noticing that they seat without any real effort? In any case (!) you should also recheck your die settings - every batch I do I a percentage check for tightness by firmly pushing the tip into a small hole drilled in my bench before I crimp - this will catch any loose rounds. Good luck

Interesting to learn a new technique thank you.

 

[1894]

My own 6.5x55 was prone to such issues but maybe not so bad. Although sooty cases are an indicator of low pressure you cannot rely on that so don’t exceed published data.
I fixed the issue by using partially full length sized once fired plus cases. This provided a better seal.
In my case the issue was worse with lighter bullets and faster powder.
Your sooty cases do look low pressure to me - the shoulder is still very round. Your clean cases don’t look high pressure to me either. A fairly sure way to test them would be to use the same load in the same case and see how many firings it takes to loosen the primer pockets. I would say 5 plus and you are fine WITH THIS LOT OF BULLETS, POWDER, PRIMERS IN THIS WEATHER. Change any and you will need to back off and recheck

 

[charlieboy-shooter]

My own 6.5x55 was prone to such issues but maybe not so bad. Although sooty cases are an indicator of low pressure you cannot rely on that so don’t exceed published data.
I fixed the issue by using partially full length sized once fired plus cases. This provided a better seal.
In my case the issue was worse with lighter bullets and faster powder.
Your sooty cases do look low pressure to me - the shoulder is still very round. Your clean cases don’t look high pressure to me either. A fairly sure way to test them would be to use the same load in the same case and see how many firings it takes to loosen the primer pockets. I would say 5 plus and you are fine WITH THIS LOT OF BULLETS, POWDER, PRIMERS IN THIS WEATHER. Change any and you will need to back off and recheck

That's a very interesting post.. Clearly I still have a lot to learn as I hadn't examined the shoulders and looked at them like that. Thank you for your insight.