Might as well have a 7mm-08 not a 7mm Rem Mag!

I've loaded for the 7Mag since the mid 60's and started using data available then. It seems that about the time the BAR started being chambered in 7 Mag the loading data changed significantly. M y loads from the past worked well and I have always loaded 1mr 4831 over a 160 for about 3100. All of my rifles liked that load.

Same results for me, I use either RL 22 or IMR 4831 under a 160 and I'm getting very satisfactory results.
My Ruger has a 22" barrel and easily reaches 3100 without pressure signs which surprises me.
 
That's funny...my 30-06 Tikka was no screamer either

Likewise the Tikka in .300WSM I had awhile back. Could swim faster.

I've found more slow 30-06s than fast ones. I wish it wasn't so, but it is. Least the 30-06 users have a coniption fit, I also have one that idles along at 2850 fps with 180s. It sort of averages out the struggle for 2600 in the rack beside it.

Back to the 7mm Rem, there's more than a few slow ones out there. I lifted this from the Speer #14 manual, it is rather interesting.

"There is quite a variation in published loading data for this caliber. Differences in cases, primers, and bullets all have an effect.This emphasizes our constant caution to always reduce loads whenever changing components from those used to develop the data.

Seldom will either handloads or factory ammunition or factory ammunition match nominal factory ballistics in a sporting rifle and there is a great deal of velocity variation among sporters in this caliber. Rifles in the Speer lab's collection posted velocities varying from 400 ft/sec under to 300 ft/sec over those posted by the SAAMI pressure barrel with the same ammo. Because of this, we have departed from our usual policy of showing velocities from a sporter. The velocities are from a 24 inch pressure."

So who's right? The guy with slow one, the guy with the fast one, the guy who has been annihilating Rem Mags with an STW for a few decades? Maybe its the guy who's fast 7/08 or 30-06 treads on the toes of someone's slow 7 Rem? Maybe they are all right for their rifle, with their loads?

You know who isn't right? Those that think that all the manuals with pressure tested data are written by timid souls with a ulterior motive to make the shooter's favorite look bad. Just as wrong are those that proclaim that nobody can get the "book" speeds. Those are often people with an old load and a new chronograph, and hurt feelings aside they are wrong too.

If your loosey goosey factory rifle chambered by a crosseyed worker with a right angle grinder doesn't put out the speed it isn't because the company lawyer hates you. You might be able to sneak a grain or two in there to pick up the slack, but you might not. On the other hand, if your tight chambered, smooooth match barrelled, blue-printed action that tends to mask pressure signs beats the book max velocity with the starting load, it might not be because you are reloading genius.;)
 
Only getting 2700-2800 fps out of my 7mm Rem Mag with 160 Barnes TSX over 59.5 grains IMR4831 (1.5 grains over Barnes max recommended)

It would seem I'm shooting a belted "magnum" 7mm-08......hmmmm

Maybe Reloder 22 or continue to push the 4831 further. No signs of pressure yet

Mike

Below is your load listed above in your post with the default settings in Quickload without setting your actual OAL and case capacity etc.

At 8.4 inches down the barrel 95% of the powder has been burnt at a chamber pressure of 35,000 psi. (green vertical dotted line 95%)
At 17.0 inches down the barrel 100% of the powder has been burnt at 17,800 psi. (pink vertical dotted line ALL BURNT 100%)
Predicted velocity in 24 inch barrel 2828 fps at 58,055 psi
To break 3000 fps at a safe pressure you would need Hodgdon H1000, IMR 7828 SSC, Hodgdon Retumbo.
H4831SC did not reach 3000 fps before exceeding max pressure of 61,000 psi.

7mm%20Ql_zps5okrkulq.jpg
 
1. Each rifle is different.
2. See number 1.
3. Brass of different manufacture or case lot is different.
4. See number 3.
Compare your Tikka's fired case to your buddies (Insert brand here) fired case. look closely at the shoulders, where they begin. Get a dial or digital caliper and measure the two diameters at the shoulder.
Weigh your cases and discard the extremes. Weigh and sort your bullets.
Does anybody do load development any more? The books are a guide, chronographs are a help, but your rifle will talk to you very honestly.
 
There is no way you can argue ballistics on this subject. The large gang of "bigger is better," can out argue anybody on this subject, if ballistics is what its about.
The practical point is which will kill game better and you realistically come up with a draw. One is as good as the other for killing game.
If anything, the advantage goes to the 7-08, because it is easier to shoot and the majority of hunters, whether they like to admit it or not, will shoot considerably better with a 7-08 than they will with a 7mm Remington magnum.
 
I shoot a 16 pounds 308 with a huge brake.
There is less recoil than on my 223
I dont finch.
What is a magnum good for if you finch so much that you cant hit paper at 100 yards..
 
I may be way off base here but I don't think going as slow as Retumbo with 160gr projectiles will be of much benefit, it is getting pretty slow in that group of powders for lighter bullets.

H450 ,H4831 ,WMR , H1000 , RL19/22 etc.... look to be about where you would want to go with that bullet weight.

You said no pressure signs yet.Manuals do have a lot of variances and one may be way lower than the other on max and min loads.

What I do if unsure is I start at the lowest published load I can find and work my way up looking for pressure signs, sounds like you have a little bit to go yet.

Don't let the chronograph discourage you, that is .308 speed with that same wight bullet but you have a higher BC , don't see people saying a .308 with 160's is under powered.

If you can get your hands on Swift Scirooco's in 150gr, try them, they will boogie woogie out of that 7RM to beat all hell and shoot laser flat and accurate.
 
The fun bit is when you get the 3k you want in the summer with rl22 et al. of temperature sensitive powders and then chronograph it in -10C or whatever temp you will be hunting in only to have lost a good chunk of fps and might not shoot as good anymore either.
 
ive seen more than a few tikkas run slow. I have 2 one is average and one is slower but not too bad at all. luck of the draw I guess. I have a browning x bolt with 23 inch barrel in 7mm wsm that will shoot nosler 140s (ballistic tips, accubonds, e-tips) at over 3200 fps and 150 gr nosler e-tips at just over 3100, some guys claim e-tips cant be pushed as fast, so I must have a fast one. powder is r-19.

I have read somewhere that tikkas lead in is cut different than most others, helps accuracy by not being so picky, but decreases velocity. no idea where I read it, it was 2 years ago or so I cant verify it.
 
There is no way you can argue ballistics on this subject. The large gang of "bigger is better," can out argue anybody on this subject, if ballistics is what its about.
The practical point is which will kill game better and you realistically come up with a draw. One is as good as the other for killing game.
If anything, the advantage goes to the 7-08, because it is easier to shoot and the majority of hunters, whether they like to admit it or not, will shoot considerably better with a 7-08 than they will with a 7mm Remington magnum.

What people should learn is that neither one of them kick and then they can get on with the business of shooting. A 7 Rem is a cream-puff, and has about the same recoil as a stupid 30-06. You know, the one that everyone seems to think is shootable by anyone.
 
I don't see any need for a 160 gr Barnes TSX in a 7RM. Heavy for caliber and monometal construction don't go well together. Bullets end up too long and eat into case capacity. Consequently the top velocity for heavy bullets is poor. I had the same experience in loading 286gr TSXs in the 9.3x62. Barely made 2000 FPS. But 286 Norma RNs ran along at 2350 with no trouble.

In the 7RM I would be inclined to go with a 140gr TSX which should hit 3100-3200 easily and be plenty stout enough to kill whatever you point it at.

There just isn't any need to run as heavy a mono as you would a conventional construction bullet.
 
I don't see any need for a 160 gr Barnes TSX in a 7RM. Heavy for caliber and monometal construction don't go well together. Bullets end up too long and eat into case capacity. Consequently the top velocity for heavy bullets is poor. I had the same experience in loading 286gr TSXs in the 9.3x62. Barely made 2000 FPS. But 286 Norma RNs ran along at 2350 with no trouble.

In the 7RM I would be inclined to go with a 140gr TSX which should hit 3100-3200 easily and be plenty stout enough to kill whatever you point it at.

There just isn't any need to run as heavy a mono as you would a conventional construction bullet.


I used to wind that bullet up to 3500 in an STW. Never once did I recover a bullet; penetration was through and through every time. Downside is I couldn't drop an animal in its tracks with anything other than a spine shot or shoulder shot that took considerable bone. Contrast that to spectacular kills with the most ordinary of bullets like 139 Interlocks and 140-150 Ballistic-tips. Following stuff around gets old, especially when it's a regular pattern.
 
Courtenayboy,

Check the barnes data on the Web. They've been updating it recently. Now v10. Most V10 data is hotter than old data. They are now listing 60.4grs as max for Imr 4831 and 2827fps. That bullet is just plain slow and their data shows there's not much you can do about it. 7 powders listed and only Ramshot magnum breaks 2900. Your IMR 4831 results are bang on to their testing.

You're still 150fps over the average 7-08 load with that bullet:p
 
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