Ideas for feeding tiny rounds?

[CubCouper]

Last winter I built myself new hunting rigs, so this winter it was time to go-small. Checking in on what others have done or seen...

I started with a 20 VarTarg project, and have added reamers for a 20 Practical, and a 5.7x28. All works in progress as I gather components. I've got 20 cal barrels, and I've got a 700 SA bolt modified to shoot the tiny 5.7 -- just haven't committed a 22 barrel to it yet.

Q: Anyone got any ideas on modifying/building a feed system for something as small as the 5.7x28 cartridge, in a 700 in particular or any other bolt gun? Its rimless and even smaller than a 22 Hornet. I've got a 700 SA bolt modified to shoot the tiny 5.7 (bushed, Sako extractor), was just going to shoot it single-shot. But I'm already thinking about following up with another featherweight bolt gun, especially if I can put a few more rounds under the bolt.

Q(Followup): Kinda got the same issue for the VarTarg build. First one is on a 700SA, but the next one deserves an action that can feed the Fireball-length case reliably. I haven't finished the Vartarg yet, but I've tested the super-short cases in some other rifles (like a 788) and found that the center-of-mass on the cartridge causes it to dive into the magazine instead of feeding up the ramp.

Rod

 

[MislMan]

You might also want to ask this question on saubier.com.

 

[snert]

I recall threads about the 5.7x28 several years ago in a 700. I think either here or on Saubier

 

[McFred]

Control round feed helps with some of that; grab the case by the rim and guide it to the breech. The CZ 527 micro mauser action came in .221 fireball as well as Hornet from the factory which might be a better platform to work from than a Rem 700.

 

[STS]

The big issue you will find with those short cases is that the dimensions of the 700 action from the feed rails to the chamber mouth are longer than the case. By the time the case reaches the mouth of the chamber it has released from the rail. Most of the time the case will end up cross ways to the world resulting in your blood pressure making it into a no go zone.

 

[SmokinJoe]

I know that this isn't what you asked about, but IMO, you would be better served to do these little guys as a single shot setup. Actions I would consider are the CZ, as mentioned above, plus Sako, Dakota Varminter (a premium action) or Cooper.

 

[steve123]

That 5.7x28 in a M700 is going to be a total PITA! Heck 20VT was annoying and why it's now a 223AI.

I'm not the greatest fan of Contenders but... and not a bad idea to try falling block actions or similar.

Seemed people were having better luck with the HK 4.6x30 brass vs 5.7x28. I was going to attempt to do a 20 cal based off the 5.7x28 and I'm glad I didn't go through the headache.

 

[NorCalMikie]

Single shot is the only way to go to curb the PITA problem. I believe it was some Coopers that were chambered for the .221 Fireball? They would be a good platform for the 20 VT. As far as the 5.7X28 or the 4.6X30, TC or Martini would be the way to go.
Tried the 17 VHA on a Savage action, found out what the PITA dealing with the brass was so it got canned!!
The 20 VT wouldn't feed/extract too good but you learn to deal with it. Single feed is the only way to go. No issues that way.

 

[JohnJ73]

I have two Ruger #3's with #1 wood chambered in 20 Vartarg for Lapua brass that I had Pacnor rebarrel this winter.

They started life as 223's so the Vartarg is an easy fit, the same ejector is made for the hornet rifles. Don't know if it will reach out there enough to grab the little 5.7 cases.

Hopefully I can make some time soon to get them to the range and give a report.

 

[Tim s]

You want a small Sako or CZ action, even the imported miniature mauser.
I have an early Cooper 38, clip fed 17 CCM which is perfect but I doubt you want to source/break up one

 

[swd]

These “fun” little projects can be real nightmares. I worked on a CZ527 converted to 5.7x28. It was a nightmare to make feed and I’m pretty good at that kind of work. The only way I could think of making a 700 feed that would be to use a magazine from something else and adapt it to it. And then there is how many hours are you willing to put in or pay for? To spend 15+++ hours and already have a grasp on what your doing would be very easy. If you have to pay for it $65+ and hour.. The common reply from guys is “well if I know that is the most it will cost” and my reply was always it’s your gun not mine. It takes what it takes.

 

[CubCouper]

Thanks for input... kinda tracked what I had discovered. I like the mini-mausers, but threading metric on my lathe is some future exercise.

I just ran across one of the tiny Cooper actions (Model 38?) this past weekend and it looked interesting. The bolt was stripped and there was no stock/magazine/etc so all I could see was that the size looked like a very cute fit for the 5.7. I'm guessing it was from an old 17ccm or 22ccm.

The plan for the 700-5.7 is just plug away as a single shot. Kind of toying with the idea of a caliber-performance test using one barrel as the control. Start with the 5.7 and establish some performance metrics, then rechamber and repeat the tests in Hornet, Fireball, Deuce, PPC, and 22-250. Just got in a 14tw Select Match that would be the victim. I've got reamers and bolts so the exercise doesn't cost me anything but time. It isn't anything that couldn't be looked up in a book, but the progression of caliber tattoos on barrel could be a conversation starter.

 

[swd]

We were really excited when we started the 5.7x28 project but sadly a 22Hornet far out performed it, lol.

 

[Bill K]

Put a single shot follower in the 700 or just feed the case single shot from lying on top of the standard follower. Seems to work pretty well in most 700 actions with the small cases.

 

[FJVance]

The VarTarg on the CZ527 might be the easiest project? A friend with a CNC lathe could thread both ends. Easily done.