22 GT for 88 ELDM Project

[urbanrifleman]

A buddy of mine said that he wanted to do a project for fun. I proposed of that we do something with the 88 ELDM. Now that you can buy Lapua and Peterson brass in 6GT, I thought it might be fun to try the 22 GT.

I have found with experience from myself and from several of my customers that the 88 ELDM shoots lights out in the seven twist at 2730 ish. I figured this is ideal spin. Doing a little math we achieve the same ideal spin rate at 3120 in an 8 twist. This should be easily achieved I would think. The 88 ELDM shoots equally well in the 7 twist at 2680 so even as slow as 3070 would be just fine in the 8 twist.

I'm not sure how long this will take as I have been very busy with our new property. But I'm going to make us matching barrels. He has a Coup de Gras action and I will of course be shooting the Kauger Arms.

 

[Scooby-93]

Looking forward to this project, what length barrels will you guys be running?

 

[r bose]

Been shooting 88's in a Palma 7 TW 30" for many years and they are lasers. In 223 I'm getting about 2875 fps. I'd be a bit leary about going much faster because last I heard the ELDM line tends to have thin jackets. The 147g 6.5mm in particular. Maybe something has changed?

 

[kyotekiller25]

ELDMs don't like much over 300K RPMs.

I shoot a lot of the .224" 75s and 6mm 108s in 8 twists at 3000fps/270K and 7mm 180s in 9 twists at 3000fps/240K and they all do just fine.

Muzzle velocity X 720 ÷ Twist = RPMs

 

[Scooby-93]

Been shooting 88's in a Palma 7 TW 30" for many years and they are lasers. In 223 I'm getting about 2875 fps. I'd be a bit leary about going much faster because last I heard the ELDM line tends to have thin jackets. The 147g 6.5mm in particular. Maybe something has changed?

I am shooting the 88’s in a 30” 8 twist at 3500fps all good

 

[urbanrifleman]

I am shooting the 88’s in a 30” 8 twist at 3500fps all good

What cartridge is that?

 

[clowdis]

ELDMs don't like much over 300K RPMs.

I shoot a lot of the .224" 75s and 6mm 108s in 8 twists at 3000fps/270K and 7mm 180s in 9 twists at 3000fps/240K and they all do just fine.

Muzzle velocity X 720 ÷ Twist = RPMs

I'll second this! Was blowing up bullets with just over 300,000 rpm.

 

[kyotekiller25]

I am shooting the 88’s in a 30” 8 twist at 3500fps all good

Careful, you're at 315K. Sooner or later you might just have 1 or 2 go poof. I've also read it's worse on a seasoned throat/barrel, and also hot barrels after long strings.

No real good reason to run bullets over 300K RPM in my opinion anyway.

 

[Scooby-93]

What cartridge is that?

22 creed

 

[Scooby-93]

Careful, you're at 315K. Sooner or later you might just have 1 or 2 go poof. I've also read it's worse on a seasoned throat/barrel, and also hot barrels after long strings.

No real good reason to run bullets over 300K RPM in my opinion anyway.

You are correct, so far so good with this. It is used as a long range vermin gun so often just single shots - no strings as such

 

[padom]

Here my go to 22GT load out of my 28" Bartlein 1-7.5 / TL3

90smk
2x Alpha brass
CCI 450
34.5gr N550
0.01 off

https://imgur.com/a/j55o3cN

 

[r bose]

I am shooting the 88’s in a 30” 8 twist at 3500fps all good

All good so far!! Get a little firecracking and some throat erosion going and it might be a problem. Scratching those thin jackets a little could make them come apart at those RPM's

 

[RegionRat]

In for the range reports.

I am fond of Dasher and GT since really good brass came available.

 

[cp255]

The 88 ELDM shot like a shotgun for me when I tried throating out my 7 twist 223. Then again I never had much luck with any 224 ELDM in my 223 bolt guns but the 88 was really bad. When I compare the 88 ELDM with the 85.5 Berger in terms of wind drift using the applied ballistics app they are almost the same. The 85.5 Hybrid is just better in every way in my opinion.

 

[urbanrifleman]

Looking forward to this project, what length barrels will you guys be running?

26 inch.

 

[urbanrifleman]

We have never had any problems whatsoever with 88 ELDMs. Quite the contrary. People love them.

90 SMK are also outstanding. They are crazy expensive now for some reason. I used to buy them cheap from RMR Reloading. They shot wonderfully. I don't see them selling them any more.

 

[urbanrifleman]

Here my go to 22GT load out of my 28" Bartlein 1-7.5 / TL3

90smk
2x Alpha brass
CCI 450
34.5gr N550
0.01 off

https://imgur.com/a/j55o3cN

Salty. That's the node I was looking for.

 

[Frankm]

My 27” 8 twist 22 GT shoots 34.4 grs of IMR4831 with 88 Eldm at 3030 fps and .5-.6 moa range. Never experimented with any other powders as I broke it in w/imr4831 and have 10 pounds of it. Friends shooting same 3 groove Lilja barrels at 27” built with same reamer used a lot of R23. Running about 35.5 grs if memory serves me right and getting 3075 ish fps ….

Fun cartridge and quite surprising; we ve shot lots of 1000-1200 yd steel and it hangs with bigger cartridges well for drop and wind drift.