Norinco CJ 95 ammunition powder and projectile measured weights

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alpining

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I pulled apart some Norinco ammunition to build some dummy rounds, and I thought I might as well take some measurements while I was at it. Some of you might find it interesting, or maybe you have your own measurements to add to this thread. If there's a thread already on the topic, please let me know, and I'll add this to it.

Type: Norinco 5.56 55gr FMJ
Stamp: CJ95
Lot#: 33
Packaging: 1120rd crate / 560rd spam can / 20rd white paper box

Sample size: 12

Lowest measured powder charge weight: 25.8
Highest measured powder charge weight: 26.0
Average powder charge weight: 25.94
Standard deviation: 0.0793
Standard deviation as percent of average: 0.31%

Lowest measured projectile weight: 54.3
Highest measured projectile weight: 55.4
Average projectile weight: 54.93
Standard deviation: 0.370
Standard deviation as percent of average: 0.67%


As you can see, the projectile weight appears to vary significantly more than the powder charge. I thought it was interesting because I have always heard the assumption that it was the variance in the powder charges that made the Norinco ammo inconsistent. If you get stacking of extreme values for both powder charge and bullet weight, then you'll get a lot of POI shift: Low powder charge plus heavy bullet, vs. high powder charge plus light bullet. If you stack the variables the other way (low powder charge plus light bullet, vs. high powder charge plus heavy bullet, you'll get high variance in chamber pressure, which accounts for the reports I've heard of variable recoil and muzzle blast (but actually produces relatively little POI shift).

The result is the same as the assumption about variable powder charges, sure: Inconsistent shooting and inconsistent feeling ammunition.

I was thinking of making some pseudo-match ammunition using the Norinco components. My plan was to pull the ammunition apart and just re-trickle the powder charges to make it more consistent, while keeping the bullet. This worked well in my previous experience with Czech surplus 7.62x39 ammunition (consistent bullet weights, but inconsistent powder charges). Seeing this data, however, I don't think the Norinco CJ95 ammunition can be made significantly more accurate without replacing the projectiles outright. However, this might be very worth doing (for someone concerned with improving mechanical accuracy of the ammunition): The powder charges are actually surprisingly consistent for surplus ammunition.

I didn't think to measure the dimensions of the bullets when I had them pulled. That would have been interesting to check as well. I'll do it on the next batch if I remember.


The powder itself is interesting stuff, I don't believe I've seen anything like it:


DSC04931.JPG


DSC04933.JPG
 
That's it alpining, great post and pictures I've never seen powder like it either a blended charge maybe, or the same powder with largely varying grain sizes flattened ball and just ball shapes.
 
Well, the power loads are tight. 0.2 of a grain is nothing. Not for FMJ at least.

Not sure about the bullets. I doubt if you measured hornady or some other FMJ bullet it would be any tighter.
I know the length of hornady bullets varies. Loaded lots of them, could never get a bang on consistent OAL.

Realistically, for factory FMJ, those measurements are pretty tight.

What you want to do, is measure the case weights, then you'll really see some yo-yo tolerances.
That and, what Norinco is notorious for that is their biggest cause of inconsistency, is the diameter of their bullets.
They are often undersized.
 
Interesting info alpining but your comment about replacing the projectiles makes no sense at all to me. If you go through all the trouble to pull bullets then buy new bullets why not just buy different ammo in the beginning?
 
Thank you for posting that.

Interesting how little variance of powder measure there really is. I'm sure guys doing large scale reloading on progressive presses arent getting tighter variations than that.

Even the bullet weights arent that far apart. I weighted Hornady 55gr FMJs and they have similar weight differences.

I'd hazard a guess that most of the inconsistencies are coming from the crappy brass.
 
cr5 said:
Interesting info alpining but your comment about replacing the projectiles makes no sense at all to me. If you go through all the trouble to pull bullets then buy new bullets why not just buy different ammo in the beginning?
Click to expand...

You may be able to weight sort the bullets would be my guess to what he was thinking.
 
Good info thanks for doing that. Since many complain that the Norc bullets are undersized could you measure that to give us an idea. Thanks.
 
What's the point of a lot of stuff we do.
Just, something interesting to do to see what happens. Why not.
I'm sure we've all done more pointless things in our life just to see what happens.

I think the real results will be from weight matching the cases, and diameter matching the bullets.
 
theDuck said:
That powder looks familiar. When I clean my are BCG I find it there. Interesting.
Click to expand...

I always find it odd that people find Norinco dirty.
It seems to burn clean and completely for me.
I've honestly never shot any premium US made FMJ, tho' to compare it too.
I've certainly never had unburnt powder that I can recall.
 
I've done some weighing of Norinco cases and they compare pretty close to 5.56 weights (averaging 5% or less more than most .223 commercially available cases).
In most instances it won't be case weight, bullet weight or powder weight variables that will make a big difference on paper - it will be the behaviour of the ball powder on ignition and run out of the bullet and loaded round that will create the majority of dispersion.

It would be interesting to see how this performs by comparing factory loads with some Mexican match - but just with pulling the 'rinco bullet and putting back a similar SMK or Hornady AMax.
 
CV32 said:
Considering the inconsistencies that are visually apparent in that powder, I am not surprised.
Click to expand...

I am guessing you have never pulled down factory ammo or used pulled down powder. They blend powder lots to maintain burn rates and pressure curves.

The biggest issue has been undersized/oversized (wrong sized?) bullets, faulty case annealing and dud primers. C77 documented this pretty well when explaining why he and other instructors were banning it from their courses. That said the accuracy of the powder charges by weight has been reported as surprisingly good by all who have measured.
 
Gunnerlove said:
I am guessing you have never pulled down factory ammo or used pulled down powder. They blend powder lots to maintain burn rates and pressure curves.
Click to expand...

I have pulled factory ammo but never used pulled powder. Most powders I have seen, regardless of source, even the ball powders, seemed to be fairly uniform in terms of granule size and shape. I have seen the Norc stuff in action, and it seemed fine, but the uniformity in those pics does appear to be a bit off to me. Maybe I am being judgmental.

The biggest issue has been undersized/oversized (wrong sized?) bullets, faulty case annealing and dud primers. C77 documented this pretty well when explaining why he and other instructors were banning it from their courses. That said the accuracy of the powder charges by weight has been reported as surprisingly good by all who have measured.
Click to expand...

I don't disagree. Sounds like you're reading more into my comment than what was actually there.
 
Conte said:
Not sure about the bullets. I doubt if you measured hornady or some other FMJ bullet it would be any tighter.
...
What you want to do, is measure the case weights, then you'll really see some yo-yo tolerances.
Click to expand...

Well, some aftermarket bullets are definitely better than others. The Nosler 69gr HPBT I have used were excellent, for example, but I might have just gotten lucky. I believe that the bulk 55gr FMJ by any manufacturer might not be so consistent.

Case weights? Probably a discussion better suited to the reloading forum, but case volume is what primarily matters, right, and this doesn't always compare directly to case weight.
 
cr5 said:
Interesting info alpining but your comment about replacing the projectiles makes no sense at all to me. If you go through all the trouble to pull bullets then buy new bullets why not just buy different ammo in the beginning?
Click to expand...

It's a good point, but we have to compare apples to apples: If I remanufacture CJ95 with a premium bullet, I'd bet that the accuracy I'd get would be more on par with premium commercial ammunition that costs $1.50 or $2 per round. I'd be saving a dollar or more per round.

Not to mention that with further tuning of bullet selection, seating depth, and neck tension to my particular rifle and chamber, I could possibly exceed the accuracy of the "best" premium commercial ammunition. For my rifle.

Or it might not work at all. It's an experiment that has to be tried to see if it will yield the desired result.
 
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