Reloading Q, twist rate and velocity related.

[WhitehouseW]

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Okay, Specs first, then the question:
"The Mut" AR15.
Stag Lower
DPMS parts
Brownells 3.5 trigger springs
Wilson 20" upper
1 in 9 twist

The Question:
Can I reload a lighter than recommended bullet weight with less powder to help stabilize it better?

I know 55-62 is optimal for 1 in 9, but I can reload 50gr or less for so much cheaper, I figure it's worth looking into.
I know that slowing the bullet down(less powder) by a grain or two is common to find the perfect load, but what if you load way down?

I know that the twist doesn't correlate to the weight as much as it does the length of the bullet, and most people are looking for the fastest bullet possible while maintaining stability, but has anyone here tried slowing a bullet way down in order to shoot a lighter bullet?

Obviously I know that reloading isn't always cheaper but I'd sure like to hurl some cheap stuff down range while keeping enough accuracy for PDOGs at 200-300 yards.

[wac220]

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You must have gotten a real good deal on 50 GR projectiles. The mill surplus are pretty cheap. In fact, loaded ammo is getting so cheap for standard plinking rounds, I only load for the matches now and shoot cheap for trigger time.

[WhitehouseW]

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Sorry, I was trying to suggest 50gr or lighter, not just 50's. The cheapest I find ammo is about 0.35c a round, but thats only when it's not sold out, which is most of the time. My rifle won't feed steel cased ammo well enough to use it.

[WhitehouseW]

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AND..... I'm an idiot amazing how 0:30s more of internet searching can make such a huge difference!

Military surplus is def way cheaper!

But, STILL CURIOUS, can I manage to load a supper light bullet like the varmint grenades with out spinning them out?

[Mortblanc]

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Why not try them and see?

You do not have to reload 1,000 rounds as a start. Buy 100, develop a load and use what works. If you can not get stability out of them you have lost $20 for 100 slugs and a couple hours work.

You could probably get a more specific answer on one of the hundreds of AR oriented forums.

[dalewick]

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I've seen commercial loads loaded as light as 40grain for 223. So I see no reason why you couldnt easily handload the same.

Dale

[dalewick]

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Great person here on the site for weapons and ammo info is Hummer, Might try PM'ing him with a specific question if interested.

Dale

[Bullet-Caster]

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Remember your AR is gas operated if you slow down (FPS) your round it may not cycle right. You mentioned steel cases not feeding right. Do you mean out of mag or cycling when fired. Think the is a video on the tube about this using Wolf steel cased ammo in short barreld AR's if I find it I will post it.

[WhitehouseW]

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I appreciate how helpful everyone is here
@buller-caster: I've had trouble in every AR I've owned with steel cased ammo including an AR10, I tried TulAmmo and some other cheap stuff, both types of ammo in all three AR's had failures to eject where the case go stuck in the chamber and had to be removed with a ramrod. The failure rate was about 1 in 10 rounds or more. I haven't tried Wolf or Brown Bear though.
@Dalewick: good call, I'll plan on getting some commercial rounds and see if they stabilize and then order the bulk

[Hummer]

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A 14" twist will stabilize the 55, 50, 45 and 40 grain bullets as will a 12, 10, 9, 8 and 7 twist. As pointed out backing off load may not give you enough port pressure to actuate the gas system properly. I would not go below published load data for bullet weights/propellant combos. Loading too low can give you spiked pressures and while they don't give pressures on the high end every shot all it takes is one to cause a catastrophic case failure with will normally bow out upper receiver and I have seen lowers receivers damaged as well due to case failures.

I have heard of multiple problems with combloc ammo of various calibers. Some have chambers large enough to accomodate the case lacquer residue which is applied so the ammo won't rust before it is fired but unfortunately lacquer will burn and chambers get quite hot. I have tested ARs to the 400F barrel temp range and with brass cased ammo they functioned fine.

The lacquer is shall we say consumed on firing as evidenced by hundreds of thousands of rounds of combloc brass seen at ranges that is rusting away so logically the lacquer burned on firing and since it is in direct contact with chamber the lacquer residue is likely to stay there. You get enough residue build up you are going to have a failure to extract.



Personally I would not consider steel cased combloc ammo and the brass cased stuff I have shot was not impressive so I pulled the ammo down.] (since it can't be reloaded easily) and lowered the propellant charge and loaded a heavier US bullet therein giving me much better accuracy.

Another problem of combloc ammo is much of it is steel jacketed ammo. Yep it looks brass but a magnet will tell you quickly if the jacket is steel with a copper "wash" on outside to prevent rust. Copper "wash" is not the same as CCGM projectiles (copper clad gilding metal) which is around .005" thick so the rifling won't cut through the copper allowing a steel on steel combination.

I was asked to examine (bore scope) a AR a couple years back with a recorded 5000 rounds of 5.56 steel jacket bullets through barrel. From the chamber in about 8 inches it looked like a normal 5000 round barrel deterrioration but starting mid bore the rifling started getting shallower and shallower and about four inches from the muzzle the lands were worn down even with the grooves. This is absolutely guaranteed to destroy accuracy. (Note: the reason the muzzle end deterriorates is the copper wash was but microns thick and it is gone in the first few inches of bore travel. This has been enountered at Aberdeen with copper washed steel drive bands on larger calibers with long barrels.) But then again if one is of the spray and pray crowd shooting at gallon buckets at 25 yards then it wouldn't be noticed but a match shooter will notice this much quicker.

A good barrel in an AR will deliver 1" groups or less at 100 yards with ammo loaded with good match bullets.