Cast 180gr in 7.62x39

WhelanLad

WhelanLad

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I have alot of Cast 311- 303 stuff, an i was wondering, Why cant i load these in the 7.62x39 as a plinker???
they are coated hard cast , .312? but have a few coatings to bring them up, or they were not resized from about .313 or somehing, trying in that Ruger 1, but i give up on them...

please tell me more.

i could Size them in a swager die??

might i have to cut the bases off them a bit an come up a bit shorter, sized? etc

assume the Length is issue ? or
 
Are your asking what concerns beside bullet diameter, overall lenght and throat lenght?
What's your rate of twist? I'd guess you'd need 1:10 or 1:11 to stabilize them.
 
wildphil24 said:
Are your asking what concerns beside bullet diameter, overall lenght and throat lenght?
What's your rate of twist? I'd guess you'd need 1:10 or 1:11 to stabilize them.
Click to expand...
not too fussed on Diameter.... it will squeeze down ;)
overall length i spose might be an issue-- powder capacity? whch powder should i use? have 4198....
throat length a bit of a potential issue- measured it once an seemed to have a bit of room to play there- ? will need to seat one in an work around it but thats where thought might be to cut some down in the lube grooves-- less length plus lighter end product?

zastava lkm85 is the gun ?
 
The primary concern with oversized bullets is the resulting loaded neck outside diameter. If there's not at least 0.001" neck clearance with the chamber neck, you risk "pinching" the neck and that can cause a significant increase in pressure.
 
Yup! As per Andy above in Post #5 - is pretty standard that a bullet should drop into a fired case neck - should not need to be "pushed" - should just drop through - shows that there was enough room in that chamber for the case neck to relax and let go of the bullet upon firing. If it does not, then you are looking at enlarging the chamber neck area or peeling the case neck walls (or using a smaller diameter bullet).
 
Andy said:
The primary concern with oversized bullets is the resulting loaded neck outside diameter. If there's not at least 0.001" neck clearance with the chamber neck, you risk "pinching" the neck and that can cause a significant increase in pressure.
Click to expand...
slipping a boolit into the fired case should give some indication of this issue though? no?
 
Potashminer said:
Yup! As per Andy above in Post #5 - is pretty standard that a bullet should drop into a fired case neck - should not need to be "pushed" - should just drop through - shows that there was enough room in that chamber for the case neck to relax and let go of the bullet upon firing. If it does not, then you are looking at enlarging the chamber neck area or peeling the case neck walls (or using a smaller diameter bullet).
Click to expand...
i posted just after you but didnt see the reply as i been sitting on the page for a while

yeah thats what i thought too!
you would say its not a Drop in....

so a sizer die /swager is in order :)
 
That "test" can give false negatives. It only applies if the fired cases were fired at a pressure high enough that the neck fully expands (and even then there will be a small amount of brass "spring-back"). I've shot cast bullets at such a low pressure that the neck only needed to be resized after every 2-3 firings (e.g. Swiss Vetterli). There was plenty of neck clearance and I would have discontinued use of that ammo if I had relied on that test.

Much better is to work from actual measurements, but you can also apply a thin layer of aluminum tape to the neck of a loaded case (and take before and after measurements), and confirm that it drops into the chamber without resistance.
 
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