I have some 5.7x28 SS197sr (40grn vmax) and was thinking about pulling the bullets and replacing them with Lehigh 32grn controlled chaos. I've seen some of the EA and R&R rounds and it appears that this would give somewhat similar performance without months of waiting and being a billion dollars. I've heard people describe 5.7 as "picky" but then they give no details. Has anyone done anything similar and if not, is there any reason that wouldn't work? My understanding is you can typically reload a factory load with a lighter bullet on their charge without issue but I'm open to that not being a real thing.

A bullet that's that much lighter (20%) would work with no problems at all.

Edited to add:

Don't know if it would be accurate or not though.

This message has been edited. Last edited by: Flash-LB,

Years back I purchased a shell plate for the 550 and did quite a lot of reloading for that round.
That case has a plastic coating and care must be given to not rupture the coating.
powder charge is sensitive and extreme care must be followed .
Work the powder charge slowly.back then there were no data in books,made my own data.
I have reloaded over a thousand or so for my F N.
Ramshot Tru blue was my best results with the v-max 40 grain and 5.6 grains.
Accurate #5 will also work and 5.7 is tops with velocity
My ladder on tru blue was 5.2 all the way to 5.8 and topped out at 1879 velocity.
I never got any 35 grain bullets and just settled with 40 grains.
I just got tired of chasing the rabbit down the hole.

I appreciate the feedback. I read a thing on another site about someone who stated removing the coating was an issue. My thought was, and I'm hoping this would help avoid it, to simply pull and retip the factory load with the lighter 32grn. I think it will be an interesting experiment and if not the investment is still cheaper than the boutique stuff. More than anything I'm looking to keep my gun and hands so I was making sure I was sticking with reasonable guidelines. I will report back with my findings at least for chronograph readings but also the next time we do a gel shoot I'd like to see how they turn out.

If you are using the same propellants that were tailored for the 40 grain projectile that may or may not cause issues. The factory propellants were pressure tested for that 40 grain VMax. The lighter Lehigh 32 bullet may suffer less than optimal performance or pressure issues if it is seated deeper than the 40 grain VMax.

Thanks for that, I was thinking of trying to hit the factory OAL for the 40s but now I'm starting to wonder if just swapping bullets might be better as I'm also reading that a lighter bullet will give slower velocities. I might try 40s and 32s and just be very careful on each. I'll be shooting over a chrony and I'll have the range to myself to grab brass and check it.

quote:

Originally posted by Anubismp:
Thanks for that, I was thinking of trying to hit the factory OAL for the 40s but now I'm starting to wonder if just swapping bullets might be better as I'm also reading that a lighter bullet will give slower velocities. I might try 40s and 32s and just be very careful on each. I'll be shooting over a chrony and I'll have the range to myself to grab brass and check it.

Actually, a lighter bullet will give higher velocities and less pressure.

You would need to at least neck size the brass before seating the new bullet or you won't have enough neck tension. I've done it with other cartridges by using the full length sizing die and back it off 1-2 turns and removing the decapping pin, it's a pain because you'll have to dump each powder charge then size it then add the powder back. It's never as easy as it seems but then again you could try it and see what happens, if it's in a semi automatic you'll probably have issues with the bullet setting back when it hits the feed ramp.

quote:

Originally posted by kend:
[...]if it's in a semi automatic you'll probably have issues with the bullet setting back when it hits the feed ramp.

Well, I'm not familiar enough with the FiveSeven or the Ruger 57, but with the P90 at least, there's no feed ramp to speak of. Bolt strips the round out of the magazine and feeds it straight into the chamber.

What is the plastic coating on the case for, specifically? I've had 5.7 dies for years and never reloaded a single round. Been collecting my brass, on the rare, rare occasion I take my PS90 out, and other people's range brass.

I usually dry tumble and the brass looks fine, but I just wet tumbled some range pickup 5.7 brass and I could definitely tell that the coating was there after it came out of the tumbler.

I had assumed one would have to use case lube to work the case, so what's the deal with the plastic coating that's already on there? Would it affect reloading, safety, or simply function in the gun somehow?