Disappointing results and a lot of soot
- Thread starter charlieboy-shooter
- Start date
I have seen this phenomina first hand while load developing/reloading at the range, with a mate who loaded 6.5x55 on Lee Collet dies, the mandrel did not allow the collet to size the neck down enough, to give good neck tension and allow pressure to build to seal the case in the chamber adequately, this is called case obturation, reulting in sooting all down the case and poor accuracy, a quick change to a borrowed set of RCBS dies cured the problem instantly
Ian.
Ian.
I did a “ladder test” for my .222Rem on Friday, using Vihtavuori N133, CCI Small Rifle primers, and 50gr PPU SP.
I got what I thought was a pretty extreme spread (using the Lee data: started at 21.3gr, ended at 22.9gr; max load is 23.0gr): nearly 4” at 100m. But a really clear and tight “node” at 21.3gr to 21.7gr. Sooty? Yes, but good accuracy; I am going to go for 21.5gr of N133 as a nice load that seems to do the job.
Interestingly, the 4 highest capacity cartridges all showed pressure signs, so I have absolutely no Intention of chasing any higher velocities.
As mentioned N160 is a bit slow. Try higher loads and with the bullet seated deeper, such as one calibres shank depth. My Swede likes N550 best with 120s, with a decent case fill and circa 3000fps and no soot.
What twist is your 222? If it's a 1:14" it may either need a shorter bullet to stabilise, or to increase velocity of your current bullet to stabilise. If already filling to case capacity you may need a faster powder.
What twist is your 222? If it's a 1:14" it may either need a shorter bullet to stabilise, or to increase velocity of your current bullet to stabilise. If already filling to case capacity you may need a faster powder.
Uncle Norm
Well-Known Member
May I suggest that you weigh a decent sized sample of your PPU bullets? I have never used them myself, however they have a reputation for significant variation. I cannot comment on the veracity of this, however I have heard it from several people I know.
I did this with the remnants of a pack of PPU 50gr SP after buying a Chargemaster Lite. I'd used cheap jewellers scales and a Lee Beam Balance previously. The spread I got was from 49.7 to 50.5gr with the bulk of them at 50.1. Don't know how that might compare with others since I've not measured any. I did it to get a batch of known weights for a ladder test.
On American forums (castboolits I think) there is a consensus that a max load on the Viht load guide is just a touch hotter than a starting load on an American based powder manual.
Have loaded to max load stated on the Viht guide as my staring load in both .270 (N160) and .308 (N140), shot brilliantly with no pressure signs.
Not felt the need to go any hotter though.
*Touches the wooden table vigorously*
Have loaded to max load stated on the Viht guide as my staring load in both .270 (N160) and .308 (N140), shot brilliantly with no pressure signs.
Not felt the need to go any hotter though.
*Touches the wooden table vigorously*
Really good point: I will do that, thank you.
Always nice to have yet another variable to add to the mix!
charlieboy-shooter
Well-Known Member
Using CCI SR premiers too. Looking back on my notes, I did some test loads when I first purchased the N133. Noted the promising load and reloaded a batch either side of that load. Turns out I used different cases before but as I had lots of Remington cases, I thought I'd used them and did this time. Was sure it was these I'd used. Lesson, is can't rely on memory and no point in making notes if I don't use them. Will try different brand and see if any difference.
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charlieboy-shooter
Well-Known Member
Twist on .222 is indeed 1:14. It shoots the 50gr Vmax just fine with the H322. As just stated above going to change cases. As 140 of different brand.
As for the Swede. I am also going to use the higher load data as clearly the other data is to low for my rifle.
Guessing it will be awhile before I will get to try any out new samples though, as the back garden is to short and the houses behind might have something to say about it too..
Sooty cases are generaly but not always a sign of low pressure and not to the extent you can over ride load data or rules.
My own experience of 6.5x55 was that N150 gave soot but N160 didn't. Regardless the thing that cured it was once fired brass from my chamber either neck sized or partial full length.
My own experience of 6.5x55 was that N150 gave soot but N160 didn't. Regardless the thing that cured it was once fired brass from my chamber either neck sized or partial full length.
you are way under pressure with 46.5gr
That could quite happily be allowing the lack of neck obturation
you want the pressure to go purple in Quickload (only an indication but you are way off)
if I read this correctly you are loading new brass?
N160 works well with heavier bullets
I would either shovel more in or move to a fasterpowder
N160 at your charge levels
note the unburned powder level (8.5%)
N160 with higher charge:
With N150
Note 100% burn
higher efficiency
purple pressure
better barrel time
That could quite happily be allowing the lack of neck obturation
you want the pressure to go purple in Quickload (only an indication but you are way off)
if I read this correctly you are loading new brass?
N160 works well with heavier bullets
I would either shovel more in or move to a fasterpowder
N160 at your charge levels
note the unburned powder level (8.5%)
N160 with higher charge:
With N150
Note 100% burn
higher efficiency
purple pressure
better barrel time
OP also had 20" barrel so probably even more in favour of N150.
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