Thread: 180 ELDM Blowing up

Originally Posted by 6x47

Jayzusss. That must be one HOT load

Yep, that must be putting the hurt on his brass and throat.

With the very high BC there’s no need to send them any quicker than 2850-2900, or to over twist them. I run them in my 7 RM at 2840 in an 8.7 twist barrel and never had a failure.

Originally Posted by 6x47

Jayzusss. That must be one HOT load

28" barrel, 2225 and mag primers. Still gets 4-5 firings per brass. He loves to make things more exciting and that load certainly is. Knocked a tahr over at 1140 though so certainly does its job

My 28 Nosler started blowing up both the 180 ELD-M’s and 195 Bergers at about 800 rounds.
The bullets that did reach the target were still accurate, but I picked up quite a few jackets of the ones that didn’t get there from the range floor.
Krieger 4 grove 1:8.

that's an interesting piece of data @Matt2308. If it only started happening after that many rounds I wonder if throat erosion or fire cracking in the bore has caused this ? roughing up the projectiles as they go through. Have you tried polishing bore with JB's or autosol ?

Originally Posted by chainsaw

that's an interesting piece of data @Matt2308. If it only started happening after that many rounds I wonder if throat erosion or fire cracking in the bore has caused this ? roughing up the projectiles as they go through. Have you tried polishing bore with JB's or autosol ?

Yes was definitely due to the rough throat, if I did another one I’d go with a 5R that should be a bit easier on jackets, although
7-800 rounds is about all the life that you’ll get out of a 28 Nosler barrel anyway.
No, I just re-barrelled to 7 Blaser and prefer it to the 28 Nosler.

Originally Posted by superdiver

Unsure twist on the rifle but are doing 3150 and no issues. Lots of rounds too( buys them 500 at a time). Wonder if it is a dodgey run?

Thats honking for a 280 isn't it?

Originally Posted by Kelton

Thats honking for a 280 isn't it?

280ai. Yes very fast, mate is shooting a smaller pill in his rem mag with alot more powder out of a 24" barrel and not close in speed. With a muzzle break it is a pussy cat too

I run 180Eldm @ 3060 in 1-8.4 twist. Proof barrel which uses a 5R type. No issues todate and very accurate. 7mm Blaser Mag. Use them 0-600m at the mo. As the step up is new no experience on animals. But I’d expect spectacular results.
Worn throats probably tear up the jacket.

Nathan Foster has done extensive close and long range testing on this projectile.

alright Ill bite....WHF are you fellas running such tight twists???
I can understand the 1 in 8 for .223 wanting to run heavies eg 80 grn.....still think may as well use .243 ...but why on earth do it in 7mm mag etc???
some of us run 170grn projectiles in bog std 1 in 10 twists with great accuracy going somewhere in mid/ high 2000s and no issue with 150s going quicker...
Ive been accused of looking for dinosaurs to hunt when using 180s in .308 for bush work.... why are you wanting such a heavy for calibre projectile???? and why are you torturing it so extremely with tight twists???
and Jit....the fella you mention ALSO mentions stupidity of extreme speed in tight twists...
maths for you..... 3000fps at 1 in 12 twist= 3000 turns per second X 60 seconds per minute = 3x6=18 add zeros 180,000rpm now make it 1 in 8 twist and you increasing that by 30% so 220,000rpm
once upon a time when the 220 swift was first being played with guys were having same issues you fellas are now...for the same reasons.
you can only swing that bucket full of water around above your head so fast before the handle breaks... projectiles are spinning so darn fast they trying to pull themselves apart the effect of that rifling most create one hell of a lot of heat too... you have ALWAYS needed a hard projectile if you want to drive it fast.... you now driving it fast AND speeding up the spin..... issues were bound to follow.
now if SOME of you fellas are having these projectiles disintergrate in mid air.....yes some arent.... how the hell can you ethically use them on anything other than paper????
its always been touchy subject re varmit type projectiles in the .224s for big game.... head or neck or crease or dont bother...how is what you doing any diferent??? yes its 180grns of little bits,but they still little bits,you have defeated purpose of going heavy....for it to stick together and penertrate deep breaking bones etc...

Originally Posted by superdiver

28" barrel, 2225 and mag primers. Still gets 4-5 firings per brass. He loves to make things more exciting and that load certainly is. Knocked a tahr over at 1140 though so certainly does its job

Ahhh..... 28” barrel will help with velocity.

Originally Posted by Micky Duck

alright Ill bite....WHF are you fellas running such tight twists???
I can understand the 1 in 8 for .223 wanting to run heavies eg 80 grn.....still think may as well use .243 ...but why on earth do it in 7mm mag etc???
some of us run 170grn projectiles in bog std 1 in 10 twists with great accuracy going somewhere in mid/ high 2000s and no issue with 150s going quicker...
Ive been accused of looking for dinosaurs to hunt when using 180s in .308 for bush work.... why are you wanting such a heavy for calibre projectile???? and why are you torturing it so extremely with tight twists???
and Jit....the fella you mention ALSO mentions stupidity of extreme speed in tight twists...
maths for you..... 3000fps at 1 in 12 twist= 3000 turns per second X 60 seconds per minute = 3x6=18 add zeros 180,000rpm now make it 1 in 8 twist and you increasing that by 30% so 220,000rpm
once upon a time when the 220 swift was first being played with guys were having same issues you fellas are now...for the same reasons.
you can only swing that bucket full of water around above your head so fast before the handle breaks... projectiles are spinning so darn fast they trying to pull themselves apart the effect of that rifling most create one hell of a lot of heat too... you have ALWAYS needed a hard projectile if you want to drive it fast.... you now driving it fast AND speeding up the spin..... issues were bound to follow.
now if SOME of you fellas are having these projectiles disintergrate in mid air.....yes some arent.... how the hell can you ethically use them on anything other than paper????
its always been touchy subject re varmit type projectiles in the .224s for big game.... head or neck or crease or dont bother...how is what you doing any diferent??? yes its 180grns of little bits,but they still little bits,you have defeated purpose of going heavy....for it to stick together and penertrate deep breaking bones etc...

Physics...the fast twist is needed to fully stabilise them and achieve the highest bc possible for better ballistics at extended ranges. I know some people run them from 1:9 barrels but they are unlikely to see the full potential of the bc.
I haven’t had any issues shooting the 180 ELD-M’s at 3060 from the 7 Blaser in a Bartlein 1:8 5R and they absolutely hammer game at extended ranges.

Originally Posted by Matt2308

Physics...the fast twist is needed to fully stabilise them and achieve the highest bc possible for better ballistics at extended ranges. I know some people run them from 1:9 barrels but they are unlikely to see the full potential of the bc.
I haven’t had any issues shooting the 180 ELD-M’s at 3060 from the 7 Blaser in a Bartlein 1:8 5R and they absolutely hammer game at extended ranges.

Yes exactly, i built my 28N to shoot the 195gr Berger so need the 8 twist barrel. Tried the 180gr eldm to see how they went. They didnt shoot quite as good as the 195s in my rifle so i stayed with the 195s.

actually realised my maths is wrong...going from 1;12 to a 1;8 is a 50% increase in spin...3 turns in 24" Vs 2 in 24" so will be 180,000 x1.5= 270,000rpm
so its like going from 3000fps to 4500fps in the forces /strain its putting on projectile....

Most of the fast spin blow ups I have seen, although my experience is limited to a couple of 22-250s, have occurred not far downrange. ie they never made the target. On the odd occassion have even seen the disintegration and it was never far out.

Originally Posted by Micky Duck

actually realised my maths is wrong...going from 1;12 to a 1;8 is a 50% increase in spin...3 turns in 24" Vs 2 in 24" so will be 180,000 x1.5= 270,000rpm
so its like going from 3000fps to 4500fps in the forces /strain its putting on projectile....

Yep MD, correct.

Easy formula is MV X 720/Twist Rate = RPM