Too fast and dangerous? 7mm Rem Mag, 180gr ELD-M, RL26

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Originally Posted by Spitfire

67 grains of RE26 with 180 ELD-M yields 2840 fps in my 7RM with a 25” 8.7 twist barrel, so yours is fast alright. With a BC as high as the 180, there’s no need to chase high velocity and diminish case life.

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Or barrel life. lol

Do you have a friend with Quickload? RL26 typically yields low pressure for most calibers compared to other powders.

Hmmmm - Running this in Quickload (without all the variables solved esp case capacity) it says your velocity with 68.0gn is around 3030 fps from your 26" barrel and pressure is in the vicinity of 68,000 - 70,000psi. SAAMI limit for this cartridge is 61,000 so I'd say you are pushing the limits. A lot of loads posted on forums analyse to a similar or greater level of pressure - but you are betting that the very much improved contemporary manufacturing processes for every component save you from a catastrophic failure.

I'm with @grandpamac that its not real sensible to be operating at that sort of level - one little element in the process goes wrong and the results range from a hell of a fright to just about dead.

All gravy if you ask me thats just off what i was getting out of my 7mm blaser same twist rl26 68gns also in a finnlight rem mag 9twist got 3050ish from memory with 175 eldx and 2225

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Originally Posted by Kelton

All gravy if you ask me thats just off what i was getting out of my 7mm blaser same twist rl26 68gns also in a finnlight rem mag 9twist got 3050ish from memory with 175 eldx and 2225

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As above, and the Blaser case has a smaller case capacity on a tikka action.
Some barrels can be up to 100 fps faster than others too

I don't know why some are getting so excited about it

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Originally Posted by Pommy

How much jump are you giving the 180's out of interest? I'm finding them a bit finicky in my 284.

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Around .030" jump, which is a lot but my Mag can only accept a COAL of 3.4 so I stick below that.

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Originally Posted by Gkp

That's fantastic!
Book max loads are very Conservative so I wouldn't be concerned.
Job done. Go out and shoot some shit!

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Thanks Gkp, that is what I was thinking too.
I have read Nathan Fosters reloading books and he mentions the same, though I know there is more experienced people than I on this forum so I thought it best to check.

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Originally Posted by grandpamac

Greetings Kiwiazonic,
If you are getting more velocity than Hornady then you are getting more pressure. I assume that with an eight inch twist it is not a factory barrel. If so this could account for part of the difference. Your additional two inches of barrel would add about 60 fps so the remaining extra velocity would equate to about 2 to 3 grains of extra powder. The max pressure for the 7 mm Rem Mag was reduced about 25 years ago due to erratic pressures in the cartridge. In my opinion, at least, primer appearance and bolt lift are worthless as pressure indicators but I would be concerned about the light ejector mark. To me this would indicate that the elastic limit of the case is near. To an old and cautious Fudd like me it is more risk than I would take but you must make your own decision. A round 3,000 fps sounds doable, You may wish to check how much flatter trajectory the extra 70 fps makes.
Regards Grandpamac.

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Thanks Grandpamac, that's some pearls of wisdom there.
That small amount of brass flow into the extractor port defiantly has me questioning the limit I'm pushing, and the days at the range were mild so maybe a hot day is all it takes to push it over the limit.
70fps does not add much if anything to the drop, though it just the point where my velocity and accuracy tightened up, nothing else in my ladder test compared to this sweet point, so it's a real head scratcher form me.

@kiwiasonic out of interest what brand of barrel are you running?

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Originally Posted by Puffin

What chronograph please and/or has the velocity been compared to any drop data yet?

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Hi Puffin, Chronograph is a Shooting Chrony - Master Beta. My speeds were tested over 2 days, 2 x 5 shot groups. Day 1 group averaged 3072fps, day 2 group averaged 3071fps.
I have only tested over the chrono, no long range validation yet as I wanted to talk to this group first before taking the development any further.
If I could get my hands on another chronograph to validate the speed the would probably help, but as you say a drop test would prob be the best way to confirm.
Attachment 145564

Nice setup. You must be stoked with that performance

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Originally Posted by Ryan_Songhurst

I have always been able to achive book max at least. However.... the other day I loaded up a pet load I have of 51.7gr 2209 with 140 Interlock for my new Kimber, this load has shoot really well in every 270 I have had, it shot well in the Kimber also, but... I loaded up a couple at the book max of 52gr 2209 (only .3gr more than the pet load) and fired off the first one, it was wildly off target compared to the lower load and the bolt was very very stiff, primer was super flat. This makes me a bit nervous about using the pet load now in this rifle so I will start again or possibly just back off to 51gr and see if its still nice and accurate. Amazes me how it can go from fine to crazy with .3gr more powder

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Hi Ryan, yes I agree it does not take much for a boarder line load to go from good to bad. This is why I thought I better check with the wisdom of the group. Even a temp change could push it over the limit.

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Originally Posted by Jit

I agree tha book max are conservative for 7RM, Ive always been at max or over after careful load development and case obsevartions. +3k with 180s is stellar for a 7RM even with 26in. That RL26 ha a hgh densirty compared to 2217 or 2225 so you dont usually get to 100%+ case loads in my experince.

You may also have fast barrel, some rifles just do. I had a 24in 7RM 9.5 twist Blaser whcih just wouldnt safley get beyond 2900 with 162s and now have a 7SAUM 8 twist with 22in which can eassliy get into the 3k with Berger 168s. I alwasy go for accuracy over velocity these days. Great result for a 7RM well done.

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Thanks Jit.

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Originally Posted by GWH

If you are not getting any heavy bolt lift, or ejector stamps on the case heads to really speak of you should be pretty ok. However you have developed this load in winter, and its likely pretty hot, so once we get into the warmer months you may find you start to get excess pressure signs with heavy bolt lift and ejector stamp marks on the brass.

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Some very valid points GWH, it was about 20 degrees in March before lockdown that I did the testing, but as you say a 30 degree day and the rifle in the sun might be all it takes to push it into the unsafe zone.

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Originally Posted by Benj

https://forum.nosler.com/viewtopic.php?f=4&t=38851

you might find this interesting. I usually search for a quickload workup of something i am looking at running which gives you chamber pressures for a given powder projectile combo and velocities. it seems to be pretty accurate.

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Wow, that is very interesting. I am way above Quickload recommendations, even Hornady have their guide above the max.
https://press.hornady.com/assets/sit...-eld-match.pdf