Backwards rifle bullets

[rc1153]

Hey guys, I was reading through a thread on arfcom about loading rifle bullets backwards. That thread broke into a discussion about aerodynamics and efficiency of certain shapes, etc. I'm trying to determine if this could be a useful method for loading subsonic 5.56 rounds. A backwards bullet would enable to use a longer (heavier) projectile as well as reduce usable case capacity right? So what do you think, do you have any experience with this? Is it even safe?

[silencertalk]

It risks not feeding as well. I think of this as more of a bolt gun trick.

[yellowfin]

IIRC this is was an old timer's trick to get an expanding load when all they could afford was FMJ bullets.

[Tin_Can_Terminator]

http://www.boxotruth.com

Search around, he did experiments with such. I think his results were to just buy good modern soft points.

TCT

[JohnInNH]

Subsonic bullet aerodynamics are different than supersonic. A backwards SMK will "fly" very well backwards at subsonic speeds. It also will have more shock power unless it tumbles then they both have the same.

If you research it you may find that this dates back to WWII

The long point pointing backwards will help to break the vacuum. I wish I had a shadow graph of the turbulence of a backwards vs forwards SMK at 1000 FPS. I think many people would be very surprised.

My backwards SMKs feed fine from the internal box in my M700.

You can very quickly tell which ammo is which.. This may have also been one of the reasons it was used during the war. I wish I saved all my links and data.

I can not attest to if a longer bullet is more stable if fired backwards. I would think so. But I have no data or evidence to prove it. The CG may be farther forward, and the tail may act to stabilize,, BUT on the other hand the blunt nose may cause more drag negating any benefit of the CG and tail drag benefits.

I am no aerodynamic engineer for sure. Maybe some expert can chime in?

[libertyman777]

I talked with Mark White about it several years ago and he says it worked well in his testing. I've never tried it though.

[DHunter]

Subsonic bullet aerodynamics are different than supersonic. A backwards SMK will "fly" very well backwards at subsonic speeds. It also will have more shock power unless it tumbles then they both have the same.

If you research it you may find that this dates back to WWII

The long point pointing backwards will help to break the vacuum. I wish I had a shadow graph of the turbulence of a backwards vs forwards SMK at 1000 FPS. I think many people would be very surprised.

My backwards SMKs feed fine from the internal box in my M700.

You can very quickly tell which ammo is which.. This may have also been one of the reasons it was used during the war. I wish I saved all my links and data.

I can not attest to if a longer bullet is more stable if fired backwards. I would think so. But I have no data or evidence to prove it. The CG may be farther forward, and the tail may act to stabilize,, BUT on the other hand the blunt nose may cause more drag negating any benefit of the CG and tail drag benefits.

I am no aerodynamic engineer for sure. Maybe some expert can chime in?

SMK = Sierra Match King?

[ranb]

I tried backwards subsonic 70 grain speer bullets once in AR 1-9 twist. The accuracy was so poor that I never tried it again. They did much better loaded the proper way.

Ranb

[JohnInNH]

Subsonic bullet aerodynamics are different than supersonic. A backwards SMK will "fly" very well backwards at subsonic speeds. It also will have more shock power unless it tumbles then they both have the same.

If you research it you may find that this dates back to WWII

The long point pointing backwards will help to break the vacuum. I wish I had a shadow graph of the turbulence of a backwards vs forwards SMK at 1000 FPS. I think many people would be very surprised.

My backwards SMKs feed fine from the internal box in my M700.

You can very quickly tell which ammo is which.. This may have also been one of the reasons it was used during the war. I wish I saved all my links and data.

I can not attest to if a longer bullet is more stable if fired backwards. I would think so. But I have no data or evidence to prove it. The CG may be farther forward, and the tail may act to stabilize,, BUT on the other hand the blunt nose may cause more drag negating any benefit of the CG and tail drag benefits.

I am no aerodynamic engineer for sure. Maybe some expert can chime in?

SMK = Sierra Match King?

Yes.. 168 gr Sierra Match King was what I shot and they were VERY accurate at close range where the wide velocity spread was NOT an issue. Vertical stringing is common with longer shots when using the over sized 308 case for subsonic loads. 30 fps ES will mean a large vertical stringing at any real distance.

The 300 BLK being a LOT smaller of a case will shoot a LOT better than a 308 subsonic will ever do.

I would not think a 70 gr SMK subsonic in a 1:9 would not be stable. How long is it.. Run the stability #s

Also remember when loading backwards you are also filling the case more and that will help reduce the ES and is/was another reason to do it. (make sure you point the muzzle up to shift the powder back to the primer)

[Wicked]

I would not think a 70 gr SMK subsonic in a 1:9 would not be stable. How long is it.. Run the stability #sr

The SMK is 69gr and is NOT stable at subsonic velocity in a 1:9 twist barrel. The bullet in backwards is not the issue.