7rm, 180 hybrid at 3030- too much pressure?

[KYpatriot]

Hello ladies and gents,

Looking for an opinion here. I have finally got a load that is both accurate and has low extreme spreads. I had a long throat 7 rem mag built, and am using 300wm mag AI mags so I can get the bullet way out there.

The load is
fed gm215m primer
in Nosler custom brass,
72.7 Retumbo
Berger 180 hybrid
Graphite lubed necks
Oal is 3.51
Velocity is 3030 on my magnetospeed, shot from a surgeon long action 26 in bartlein 8.5 twist.


This is over the book max but I am running a longer oal. Primers and pockets look good after 3 loads but I get a slight ejector spot on the case, nothing raised just a slight ejector polish. No heavy bolt lift or other signs.

I have mac computers. If someone could point out how to get quickload to work for them I'd buy it. Will QL work on a virtual office suite? I am not computer savvy.

Can someone with QL let me know if this is way out there or not? I don't want to buy a new computer just to use QL but i really want it and would buy it if I could run it somehow.

I am hoping it is reasonable since it is half moa out to 900.
Thank you very much.

 

[idaho elk hunter]

I am using the same OAL with a 28 in Broughton 1 in 9 twist. Barrel is nitrided and I hex coat the bullets. Switching to Win Mag primers is putting me at 3150 to 3158. I start seeing big pressure signs at 3200. Pressure goes up very quickly with Retumbo

 

[c_bass16]

To use QL on your Mac...the best way to do it is to fire up Bootcamp and load a Windows Parallel.
Google it if you don't know what that means.

Basically it partitions your hard drive and allows you to boot your mac up and run it as a Windows PC instead.
Restart it, and re-boot in OSX whenever you want.

As for your velocity in question. I wouldn't be to worried about it.

I run THE EXACT SAME OAL 3.51. (but I measure to the ogive)

Fed 210 GM Match
78.4gr of RL33
25" barrel at 3105 with VLDs and 3066 with hybrids with my 8.5 twist Rock Creek

Only "pressure" signs I get is the bolt gets hard to lift after about the 3rd firing. Just need to Full Length resize it and it's all back to good.

 

[dkhunt14]

There is a big difference in COAL and Base to ogive. Base to ogive at the same number would be less pressure because the bullet is out a lot farther. Ejector mark is sign of pressure. Broughton barrels are usually faster and clean easier. Matt

 

[Lefty7mmstw]

2900 fps is about all I'd take a 175-180 to in a 26" bbl'd 7rem, but I'm one of the get a bigger gun fella's who will not run his rifles over the low 60 K psi range no matter what. I'll leave a bit of performance on the table to get more life out of my rifles and brass. Ejector marks will usually not show up until 70,000 psi or so...

 

[idaho elk hunter]

My 3150 fps is derived with 66300 psi. the 3200 fps is WAY over the 70000 psi. It is all in the way you have the barrel built. A 5c Broughton will outpace most barrels. Combine that with the 3.50 coal, nitrided barrel, hex boron bullets, let alone a 28 inch barrel, you will get impressive results every time. The 180 Berger will produce less pressure than the 175 ABLR due to bearing surface. RL 33, H870, N570, and all the SLOW burning powders do not work. The 3.5 coal changes everything. H4831, H100, and Retumbo will get you up there in fps with the H1000 probably being the best due to muzzle pressure and internal ballistics. I used the Retumbo example just because I have 40 loaded ad is the only one I have pressure tested.

Belted mags will handle 65000 +- pressure all day long an will give 4 loading per brass.

Many will tell you this is unsafe but done correctly with these changes it works. Keep in mind they are probably overlooking the 3.5 coal.

I have built 4 of these rifles and they all perform the same. If you do not have the exact set up I would recommend to use the hex coated barrel ad bullets and work up from there.

Win Mag primers are a must. On average they gave me 20 fps more and a lower SD.

 

[KYpatriot]

Thanks guys. I don't want to be up into 70k if that is really what ejector marks mean. I was hoping someone could run the QL on it until I get my virtual windows machine up and running.

I also realize I probably should have put this in the reloading section-sorry mods.

 

[brentc]

I'd say if the load runs great, use it. Especially if you're not getting much of an ejector mark on the soft Nosler brass. I've gotten very similar results in mine when running a max charge of Retumbo.

 

[c_bass16]

There is a big difference in COAL and Base to ogive. Base to ogive at the same number would be less pressure because the bullet is out a lot farther. Ejector mark is sign of pressure. Broughton barrels are usually faster and clean easier. Matt

No ****.
I keep records of my length to the ogive....but I measured a loaded round OAL and it is exactly the same as his.