Degraded Ballistics with a Scratched Bullet?

[SubieGuy4]

I take my AR with me when I leave the house every day, which means each morning I have to rack the chambered round out for it to be legal in the car. When you rack the round out of an AR a few times, the bullet will develop some noteworthy scratches (enough to feel with your finger). I'd be surprised if anyone here has any factual information about the effects of this, but I'd be curious to hear any scientifically-based reasons why people do or don't think this would effect precision ballistics.



Note, if these were XM193, I wouldn't care because they aren't precise anyway. I use MK262 Mod 1, which is MOA ammo from a good gun. I read that Sierra didn't even want to agree to put a cannelure on the SMK 77gr OTM bullet, for fear of degraded ballistics. But that they agreed to as it was a contract requirement. Knowing that, I'd think you'd loose something if the bullet is scratched, but I don't have a great sense of exactly how aerodynamics work right at the bullet. For reference, my gun will shoot sub MOA with these when they're fresh out of the box, so even a small effect would be significant by comparison.

 

[bawannabuck]

The primer is the bigger problem.

 

[SubieGuy4]

The primer is the bigger problem.

I assume you're referring to the small dent you get when you chamber the round. Do you mean it creates an ignition problem later or that there's a risk of a slam fire while chambering?

 

[bawannabuck]

the dint will degrade the primer after many chamberings.

 

[SubieGuy4]

the dint will degrade the primer after many chamberings.

Gotcha. Not too worried about that. I lock the bolt, hand feed the round, ride the bolt forward, then put it in battery with the forward assist (to avoid denting the primer). Less fun than racking on in, but it keeps me from having to cycle out about $25/mo in expensive ammo.

I actually do something similarly when I remove the round in the morning, in that I keep it from ejecting with my finger so it doesn't scratch. I only started the thread because I'm curious if I should be concerned if I do happen to scratch one.

 

[M1911]

My recommendation would be to just store it at all times with an empty chamber, and practice picking up and chambering a round.

 

[SubieGuy4]

My recommendation would be to just store it at all times with an empty chamber, and practice picking up and chambering a round.

Respectfully disinterested in that practice. Unless I have a legal or clear safety reason not to, I keep all my guns chambered. Having to cycle out rounds for transportation is at worst an expense and a mild hassle. Not in the habit of pinching pennies or making life a tiny bit easier at the expense of readiness. Just my opinion.

 

[M1911]

Respectfully disinterested in that practice. Unless I have a legal or clear safety reason not to, I keep all my guns chambered. Having to cycle out rounds for transportation is at worst an expense and a mild hassle. Not in the habit of pinching pennies or making life a tiny bit easier at the expense of readiness. Just my opinion.

I keep a round chambered in my handgun, but then I'm allowed to transport it loaded. It is illegal in most states to transport a loaded long gun. So if you keep your long gun for defense at home and in your vehicle, you know have to deal with it possibly being in two different states of loading: 1) in the home, chamber loaded, 2) in the vehicle chamber empty. Keeping it chamber empty simplifies things -- you always know the status when you pick it up.

Personally, I think you will be more "ready" if your gun is always in the same state of readiness. If it is sometimes chamber empty and sometimes chamber full, that is a prescription for failure.

 

[drgrant]

Respectfully disinterested in that practice. Unless I have a legal or clear safety reason not to, I keep all my guns chambered. Having to cycle out rounds for transportation is at worst an expense and a mild hassle. Not in the habit of pinching pennies or making life a tiny bit easier at the expense of readiness. Just my opinion.

Then in NH get an AR pistol and not worry about it. If cost isn't an issue you could get another rifle just for the car/truck/whatever.

-Mike

 

[SubieGuy4]

I keep a round chambered in my handgun, but then I'm allowed to transport it loaded. It is illegal in most states to transport a loaded long gun. So if you keep your long gun for defense at home and in your vehicle, you know have to deal with it possibly being in two different states of loading: 1) in the home, chamber loaded, 2) in the vehicle chamber empty. Keeping it chamber empty simplifies things -- you always know the status when you pick it up.

I suppose that's sound logic. Unloaded guns at home make me slightly uneasy though (I like to know for sure that all of them are in the same condition at home so there's no question), so I prefer things be chambered at home. Especially since this AR is a bed-side gun at night.

When it's in the car I don't think of it as a quick reaction gun. My carry pistol is what I'd use if I needed something in a hurry while away from the house. The AR is for the difficult-to-imagine situation where there's time to put on armor and ready the gun, but still a need to use it. I suppose something like a natural disaster / might have to fight your way home scenario. The home/property defense role is what I see being the more likely use, so I leave it conditioned for that.

Then in NH get an AR pistol and not worry about it. If cost isn't an issue you could get another rifle just for the car/truck/whatever.
-Mike

That was the plan right up until the all knowing ATF pulled the crap with the SB15 brace. I was going to do a truck gun setup that would be an 11.5" with the brace so I could keep it condition 1 in the car. That dream sailed away with their new nonsense rules. Now I have to ask which is the worst situation... Rack one in and use it as intended, or Have a pistol with brace, shoulder it against the law, and some guy's cellphone video gives the ATF what they need to jail me. I'm all for ignoring technicalities when life and death is on the line, but these days a new gunfight video shows up on LiveLeak every day. Wouldn't want to ignore that technicality and be one of them.

 

[PaulD]

My recommendation would be to just store it at all times with an empty chamber, and practice picking up and chambering a round.

Yup, or carry it with the safety on, bolt open.

 

[M1911]

Yup, or carry it with the safety on, bolt open.

Bolt hold open on AR15s is not secure. Tap the buttstock on the floor and the bolt will close.

 

[Palladin]

get another AR for the house, call John at Overland Safety, get a setup for the car and leave the thing locked in there on an electric release.
http://www.overlandsafety.com/products.html They're up by Manchester.

I had one.

 

[EddieCoyle]

You could shoot it and find out.

My experience has been that 'scratches' on the sides of the bullet have no effect, but damage to the base will throw it off big time.

 

[Steve Marshall]

You're worried about accuracy but considered an AR pistol? Does not compute.

 

[drgrant]

You're worried about accuracy but considered an AR pistol? Does not compute.

here we go again....

 

[Fixxah]

No noticeable effect imo. Do you frog lube?

 

[mac1911]

You could shoot it and find out.

My experience has been that 'scratches' on the sides of the bullet have no effect, but damage to the base will throw it off big time.

I been pleasantly surprised at some of the groups I have shot with banged up tips.
There are someone posting out there on the web with people actually damaging tips on purpose to test.
No they are not precision groups....all though I did see a gent on the line during a cmp/nra service rifle shoot cut the tips of his a max bullets to fit in the mag for rapids ( forgot his mag length stuff)
He still managed to clean the target....
If the ammo is being used for defensive nature one would think it's ballistics would not be hampered enough to loose minute of target efficiency.
http://www.theboxotruth.com/the-box-o-truth-49-damaged-bullet-accuracy-and-the-box-o-truth/

 

[crazymjb]

I suppose that's sound logic. Unloaded guns at home make me slightly uneasy though (I like to know for sure that all of them are in the same condition at home so there's no question), so I prefer things be chambered at home. Especially since this AR is a bed-side gun at night.

When it's in the car I don't think of it as a quick reaction gun. My carry pistol is what I'd use if I needed something in a hurry while away from the house. The AR is for the difficult-to-imagine situation where there's time to put on armor and ready the gun, but still a need to use it. I suppose something like a natural disaster / might have to fight your way home scenario. The home/property defense role is what I see being the more likely use, so I leave it conditioned for that.



That was the plan right up until the all knowing ATF pulled the crap with the SB15 brace. I was going to do a truck gun setup that would be an 11.5" with the brace so I could keep it condition 1 in the car. That dream sailed away with their new nonsense rules. Now I have to ask which is the worst situation... Rack one in and use it as intended, or Have a pistol with brace, shoulder it against the law, and some guy's cellphone video gives the ATF what they need to jail me. I'm all for ignoring technicalities when life and death is on the line, but these days a new gunfight video shows up on LiveLeak every day. Wouldn't want to ignore that technicality and be one of them.

So if you admit it may take time to access... why not leave it with an empty chamber and practice racking it?

I dunno dude unless I was on patrol my rifle in Afghanistan always had an empty chamber.

Not saying one is right or wrong, except for a carry gun which should always have a round chambered.

Mike

Sent from my cell phone with a tiny keyboard and large thumbs...

 

[mac1911]

get another AR for the house, call John at Overland Safety, get a setup for the car and leave the thing locked in there on an electric release.
http://www.overlandsafety.com/products.html They're up by Manchester.

I had one.

that is a pretty cool set up but does it pass the locked in a case test for MA....

 

[SubieGuy4]

get another AR for the house, call John at Overland Safety, get a setup for the car and leave the thing locked in there on an electric release.

Definitely planning on a second rifle for the car when funds allow. Not into a locking rack for the car though. I just throw the rifle in the back seat.

You could shoot it and find out.
My experience has been that 'scratches' on the sides of the bullet have no effect, but damage to the base will throw it off big time.

Ya in the long run I think I’ll have to. I’m thinking in the spring I may move my only magnified optic over to my AR and use it to do some shooting for groups at 200 yards. Scratch up a set of bullets and compare groups with the out-of-the-box rounds.

You're worried about accuracy but considered an AR pistol? Does not compute.

Myth. As long as the bullet is going fast enough to be stabilized by the twist, an 11.5” gun can still post up MOA accuracy.

No noticeable effect imo. Do you frog lube?

I do frog lube, why lol?

 

[drgrant]

that is a pretty cool set up but does it pass the locked in a case test for MA....

If the trunk is locked you have a secure container. Not to mention the OP isn't from here, so not sure why we're talking about MA crap.

-Mike

 

[Dradian]

Those scratches are minor compaired to what the bullet will look like after going 3000fps through a rifled barrel.

 

[SubieGuy4]

Those scratches are minor compaired to what the bullet will look like after going 3000fps through a rifled barrel.

I had considered that. Obviously the bullet picks up the rifling grooves, but those are also in line with the wind as the bullet spins through the air at the same rotational rate as the rifling. So to my mind that shouldn't have as much effect as scratches that don't follow the spin.

 

[Dradian]

I had considered that. Obviously the bullet picks up the rifling grooves, but those are also in line with the wind as the bullet spins through the air at the same rotational rate as the rifling. So to my mind that shouldn't have as much effect as scratches that don't follow the spin.

I still think you're over thinking it. Btw, are you concerned about its performance in a self defense situation or at the range/hunting? Two very different situations.

 

[SubieGuy4]

I still think you're over thinking it. Btw, are you concerned about its performance in a self defense situation or at the range/hunting? Two very different situations.

Just concerned with accuracy (so it doesn't make much difference). Not worried about terminal ballistics being affected. The gun is intended for defense. I use the rounds I do because they're capable of MOA accuracy from my gun. If blemished bullets degrade that to minute of torso at 250 yards, then I just want to know that I can no longer count on MOA accuracy from the scratched ammo.

I wouldn't call this a big concern of mine. It's mostly academic and just something I want to be accounting for. It just makes the difference between me putting a scratched round back in the mag, or shooting it during a range session to get rid of it.

 

[Dradian]

Just concerned with accuracy (so it doesn't make much difference). Not worried about terminal ballistics being affected. The gun is intended for defense. I use the rounds I do because they're capable of MOA accuracy from my gun. If blemished bullets degrade that to minute of torso at 250 yards, then I just want to know that I can no longer count on MOA accuracy from the scratched ammo.

Gotcha. Sounds like this would be a fun test. Shoot both rounds at two different targets see what you get.

I hope you never have to explain to a jury why you needed to take a 250 yard "defensive" shot

 

[SubieGuy4]

I hope you never have to explain to a jury why you needed to take a 250 yard "defensive" shot

Ya like I said in a previous post, it's not even for defensive really. It's a "fight my way home" gun. The circumstances in which it would be the appropriate weapon to employ are hard to even think up, never mind calculate the odds on. I'm talking 3 hours from home and a natural disaster happens on a scale that things quickly plunge into near anarchy, blah blah blah. There's no such thing as a 250 yard defensive shot in the civilian life that we know today. It would have to be a wild circumstance. I'd just rather be prepared for it than not.

 

[Dradian]

Ya like I said in a previous post, it's not even for defensive really. It's a "fight my way home" gun. The circumstances in which it would be the appropriate weapon to employ are hard to even think up, never mind calculate the odds on. I'm talking 3 hours from home and a natural disaster happens on a scale that things quickly plunge into near anarchy, blah blah blah. There's no such thing as a 250 yard defensive shot in the civilian life that we know today. It would have to be a wild circumstance. I'd just rather be prepared for it than not.

I hear ya, just having a little fun.

If you decide to test the rounds, let us know how it turns out.

 

[SubieGuy4]

I hear ya, just having a little fun.

If you decide to test the rounds, let us know how it turns out.

Ya I'll try to remember to. I've never put a magnified optic on my AR but planned to try this Spring to test accuracy anyway. I'll be sure to try this.