My new build for ELR

[Scotchmo]

Actually, a rebuild. I had built a .257 ELR air rifle specifically for the ELR Magnum/Bigbore slug matches such as those at RMAC and EBR. It did great, but new rules at EBR necessitated an upgrade. Also, there have been instances where target distances have started to exceed the 300yds that the gun was originally designed for. The .257 was shooting 71gr slugs at 990fps. The “new” 7mm will shoot 100gr slugs at 1020fps. This is intended to be a 400yd rifle. The object being to hit a 4moa target on the first shot encounter at any distance out to 400yds. If this new barrel is as accurate as the .257 barrel, I'll be satisfied.

 

[mercado]

Looks great.. how long is the barrel..? That is 7mm 1-18 ..?

 

[Scotchmo]

48.25" long, 7mm, 1:14

The rifle is about as heavy as a Barret 50 BMG, and as long as a Kentucky Longrifle. The barrel liner even came from Kentucky!

 

[Geezerhood]

I like the look! The brake looks quite a bit like a Barret 82A1 style. I am assuming its purpose is as an air stripper or does it reduce rearward movement of the rifle as well?

 

[steve123]

That's pretty cool Scott!!!

 

[Sqwirl57]

Very cool! Whats the electronic doohicky on the left side?

 

[Scotchmo]

I wanted something to protect the crown/muzzle. I put the brake on because it looked appropriate. Recoil is not that much. I have yet to see how the brake works. So far I've only shot over the chronograph sans the brake.

The "electronic doohickey" is the control box for the electronic hammer/solenoid. Sort of like a Daystate, but no computer. Hammer strike is controlled by turning the potentiometer through that hole on the side, using a small screwdriver.

 

[A&P251]

Is the upper receiver cast as one piece with the scope rings?

 

[Sqwirl57]

Wow that is really really cool. If you donr mind me asking, how much did this project run?

 

[ScottEnglish]

After you win ELR, they will change the rules again.

 

[Scotchmo]

Is the upper receiver cast as one piece with the scope rings?

Yes. Investment cast.

See “lost PLA”.

 

[Scotchmo]

Wow that is really really cool. If you donr mind me asking, how much did this project run?

I’m not sure. About $3k of parts (including scope) and materials in its present form, maybe another $7k of other parts/support equipment leading up to it (smaller bottles, regs, barrels, molds, Labradar, compressor, etc.) all which I needed to do this project, but still have and could use on other airguns. And many hours for design/build/test. And more hours of testing still to come.

 

[LewisP12]

Thank you for sharing your build.

Have you had a chance to visit the shooting range?

 

[Scotchmo]

Thank you for sharing your build.

Have you had a chance to visit the shooting range?

I spent a couple hours at the range yesterday. Tore it down last night to fix/change a few details. I’ve settled on a tune for EBR. Spent three hours at the range today. Currently running regulated at 2650 +/- 50psi. 106gr slugs at 992fps average (230fpe) are looking best so far. About 1.5moa five shot groups on paper at 200m. Not quite as accurate yet as the .257 barrel, but able to hit high power pig silhouettes at 300m for most shots. Even knocked down a couple. Still working on DOPE.

 

[A&P251]

Yes. Investment cast.

See “lost PLA”.

That’s pretty interesting. I’m familiar with investment casting, although I haven’t done it myself. But, I haven’t seen scope rings that were integral to the receiver before. Looks good! And I imagine there isn’t any fear of it getting knocked off zero.

 

[sasquatch]

Holy smokes the air capacity. That thing is wild

 

[Flintsack]

That is most certainly the Tyrannosaurus Rex of air guns. I’ve often thought 7 mm would be the ultimate caliber, that or 6.5.

Irregardless, that is the ultimate Rifle.

Mike

 

[beerthief]

as a 10 meter gun it might take the target and stand down

Nice work

 

[Scotchmo]

That is most certainly the Tyrannosaurus Rex of air guns. I’ve often thought 7 mm would be the ultimate caliber, that or 6.5.

Irregardless, that is the ultimate Rifle.

Mike

Thanks. A .257 has a 6.5mm groove diameter. A 6.5mm Creedmore has a 6.5mm bore diameter. At 160fpe, the .257 is a great caliber for long range airguns. I needed >200fpe. It's just easier to get there with a bigger bore, so that's why the switch to 7mm.

I eliminated the brake, and added some camo accents. I also went back to all analog pressure gauges which are easier to read in the sunlight.

 

[Scotchmo]

I'm working on getting better BC data for the 106gr slug. I went to the range this morning and had a calm day. I took 40 shots with the 106gr slug, and most registered OK on the Labradar. I shot two five shot groups at 200m. 1st group was barely on paper but under 1moa in diameter. I dialed in another 1moa of elevation and the 2nd group was closer to center and about 1.12moa in diameter. Velocity spread wasn't as bad as shown since the 745fps was a bad reading, but it still could be better.


106gr, 200m

106gr 200m

106gr