7mm Rem. Mag. load help

[41mag]

Hey Bart,

Just reading through I saw your post on the 1-n-1000 folks and groups, I must say for a LONG time I thought I was special. The folks always told me I was 1-n-a million, now I see I am only 1-n-1000.

I have a more or less stock Sendero in 7RM that has turned in some VERY impressive groups over the years using the Hornady 162's and RL-19. I've taken some nice deer and plenty of hogs with it.

My concentration has now turned to my STW to see if I can get those same SPBT's to group with it.

Nothing against the 7 RM by any stretch, I will be breaking out the 139 - 150's for it as soon as I get the STW up and running. No sense having the same going in both. I figure the RM will be great for the oldest grandson to reach out on hogs and yote with as he grows into it.

 

[idaho elk hunter]

Please be aware of internet knowledge!! ALOT of people read and study the internet on a subject they are interested in and then call themselves experts on the subject with little or no real experiences in the field. I see this alot with load development. Repeat bullet names that are big just because of BC and not intended for hunting.


I can tell you that if you use alot of these recommended loads you will shoot impressive 100 yd loads. But at 100 yds you might as well be shooting a 30-30.

You have a 1 in 9.5 twist barrel.. At longer ranges the bullet will lose its gyroscopic ability to spin and start to tumble. You need to stay away from the heavy long BC bullets if your going to be accurate at long ranges. Even the Hornady 162 A MAX recommends a 1 in 8.5 twist,, Barnes 168 LRH a 1 in 9 twist, The "FAMOUS" Berger 180 is the best with a 1 in 8.3 twist but will work with a 1 in 9 at shorter ranges.

I would look at the 160 gr Accubonds down to the 140 higher BC Hunting bullets bullets. These will stabilize and Be very deadly on big game with good shot placement.

Mid power primers will be a little more accurate but AGAIN we are hunting. NOT benchresting.. I a COLD hunting situation I would rather have a reliable igniting primer, Not a squib load With a bad ES.

Powders are far and wide for the 7mm mag but the most accurate will be the 4350 with the best for velocity will be the 4831. There is alot of great slower burning powders out there with higher velocitys but they work with the heavier bullets that will not stabilize at long range in your application.

Remember the internet is a great place to have fun. But a quick phone call to the manufactures ( EXPERTS) can get rid of alot of Bullsh1t!

 

[Shootin4fun]

You are getting great accuracy. If I had a load shooting 150g TTSX (great bullets!) into 1/3 MOA groups, I'd stop load development, ignore the black on the necks, get some long range data for the scope table, put the rifle away till hunting season, and save some barrel life for hunting.

Fitch

+1 on that! Your post is very helpful in its detail Sako, thanks. I am starting to work up a Barnes hunting load for my 7mm RM. This is for boar and deer so I don't need the heaviest bullets. (Not going for a 600 lber...I want a moderate one for better meat) I'm thinking the 140 or 150 tsx or ttsx.

Looks like 4831 or 4350 will work for these weights and I have some of both.

I have black stains around the necks on a 243, but never thought it was a malfunction of any sort. I figured because its the valve through which all the gasses must pass / heat from pressure. The gun is a tack driver anyway and I get 9+ reloads on those cases.

 

[brentc]

The "FAMOUS" Berger 180 is the best with a 1 in 8.3 twist but will work with a 1 in 9 at shorter ranges.
!

Define short range. If by definition you mean that consistent hits on an MOA sized target at 1120 yards with berger 180s out of a 9 twist 7RM at 500 ASL is good short range performance I'd say you've made a valid point.

I don't agree with a lot of what you said in your post mostly because I know different. That 1 in 9.5 will absolutely stabilize 168 VLDs and there is absolutely no reason you can't use powders slower than the 4831s. H1000 and Retumbo are extremely well documented powders for producing animal dropping loads at ranges most guys dream of shooting.

For the OP a known performance combo is if you take a bag of fresh Winchester cases, prime them with a CCI 250, drop 70.7 grains of H1000 +/- a tenth and seat a 168 VLD to touch the lands you'll have a 1/2 MOA capable load that runs approximately 3025 fps.

 

[Marble]

I don't shoot 1000 yard targets, but would like to. I have killed several elk and deer in 450-550 yard range with my 7mm. I used to shoot a 140 grain Trophy Bonded bear claw (late 90's) but switched to the Scirroco 150gr bullet. I have loaded for this bullet in four different 7mm's and all have liked the bullet, three of them were A bolts, one Rem 700. @ 68 grains of RL 22 in a 26" bbl, my gun shoots ~3280. The other three guns prefer, because of pressure and accuracy, 67 grains of RL 22. The 24" Rem 700 shoots ~3000, the other 26" bbl shoot ~3150. It's proven to be a really good bullet that cost around .60 per bullet.

I'm sure other powders will work. And I will have to experiment since I can't find any RL22.

Remember to start low and work your way up in loads. I cant say why my gun likes the hotter load, or why its more accurate and there is no pressure issues, compared to the other three, but it does.

 

[Skookumchuck]

I am getting 1/2 moa with 150g TTSX 69.5g H1000 CCI LRM primers seated as long as my mag will allow. Going to go try it out on a Mountain Goat tomorrow.

 

[snowpro440]

Please be aware of internet knowledge!! ALOT of people read and study the internet on a subject they are interested in and then call themselves experts on the subject with little or no real experiences in the field. I see this alot with load development. Repeat bullet names that are big just because of BC and not intended for hunting.


I can tell you that if you use alot of these recommended loads you will shoot impressive 100 yd loads. But at 100 yds you might as well be shooting a 30-30.

You have a 1 in 9.5 twist barrel.. At longer ranges the bullet will lose its gyroscopic ability to spin and start to tumble. You need to stay away from the heavy long BC bullets if your going to be accurate at long ranges. Even the Hornady 162 A MAX recommends a 1 in 8.5 twist,, Barnes 168 LRH a 1 in 9 twist, The "FAMOUS" Berger 180 is the best with a 1 in 8.3 twist but will work with a 1 in 9 at shorter ranges.

I would look at the 160 gr Accubonds down to the 140 higher BC Hunting bullets bullets. These will stabilize and Be very deadly on big game with good shot placement.

Mid power primers will be a little more accurate but AGAIN we are hunting. NOT benchresting.. I a COLD hunting situation I would rather have a reliable igniting primer, Not a squib load With a bad ES.

Powders are far and wide for the 7mm mag but the most accurate will be the 4350 with the best for velocity will be the 4831. There is alot of great slower burning powders out there with higher velocitys but they work with the heavier bullets that will not stabilize at long range in your application.

Remember the internet is a great place to have fun. But a quick phone call to the manufactures ( EXPERTS) can get rid of alot of Bullsh1t!

This post cracks me up ......lmao,

 

[Shootin4fun]

Re: 7mm Rem. Mag. load HELP!?

Hi Guys,

I know this is a paleolithic thread but I experienced something strange yesterday and want to hear your esteemed thoughts on the matter. This might be a bit long but you'll see my reason for concern. In a nutshell, I'm getting much higher velocities than expected.

My Savage 114 American Classic 7mm RM, 24" barrel...First of all I'll say that I almost gave up on this gun because I had not mastered the recoil over the first 80 factory rounds I put through the tube, and as a result got scope bit several times. I was thinking of selling it.

Federal Blue box factory rounds chronoed out 20 - 40 fps lower than advertised on the box depending on bullet weight. Groups were nothing to be ecstatic about, always about 1.7+ moa. (Off of led sled and afore mentioned poor recoil handling with bipod.)

After getting some brass stocked up I loaded some Hdy 139 BTSPs; the best charge/group had better results than factory but not much. Main thing here is that VELOCITIES were as EXPECTED in various manuals. 3050 or so with 62.6 gr IMR4831. Temp 68 degrees. Accuracy still unsatisfactory.

Then after a year of dormancy, I decided to cut to the chase for a hunting round and try some Barnes 140 TSX. I put put together a batch of test rounds, incrementing .3 gr on each, the round exactly as Barnes says in terms of OAL, .050 off of lands, primer (Fed Match Mag) starting with 62.0 gr IMR4831 (NOTE; Barnes charge range is from 57.0 - 63.0 while Hodgdon & others say 61 - 65 for a 140gr bullet. From past experience I know to push Barnes on the higher end for accuracy.) . All charges weighed very carefully.


Meanwhile I also decided to change my shooting style and wrap myself around that bad boy like a python so it wouldn't bite back. Shooting off a bipod and iron table with a little potential bounce in 5 - 20 mph changing winds here's what happened and why I'm concerned...

.1"-.2" x .5" - .6" four shot groups @100. OKAY-GOOD in the short range accuracy dept. Attached picture is 4 shots ea. except center is 2 shots (2 shots on another target hold the .5" group.

Perhaps velocity spreads may be problematic at longer ranges? 80 degrees outside.

VELOCITIES:
62.0gr 3190-3300 FPS AVG 3230 ES 110 SD 50

62.3gr 3220-3284 FPS AVG 3252 ES 64 SD 26

62.6gr 3226-3427 FPS AVG 3295 ES 191 SD 89

62.9gr 3259-3276 (only 2 rnds chronoed) Av 3267 ES 17 SD 12

So what I'm worried about is velocity & pressure. No dramatic pressure signs but some primers have a little welling up around them. Easy bolt open, no ejector marks or brass flow. These velocities are about 150+fps from what Barnes says you should get, and 200+ what Hodgdon, RCBS, and Lyman manuals say for other (than Barnes) 140gr bullets.

What do you guys think?
Why the higher velocities? Is s it safe? Also, why so high ES & SDs ?? Air temp shouldn't affect it that much. I've used barnes in other calibers and they don't run much faster at the same charge level as copper jacketed same weight, though pressures are probably higher. I do run them hotter than copper jacketed because they group better at the high end.

What about throat erosion?

lightbulb Now that I know this rifle is a shooter, I want it to last a while!

P.S. It never turned around and bit me with the python hold.

 

[idaho elk hunter]

Terry Miller,,,Terrys Gunsmithing,,,Twin Falls Idaho,,,$125 for a quality brake that is the best I have used.

 

[Shootin4fun]

Terry Miller,,,Terrys Gunsmithing,,,Twin Falls Idaho,,,$125 for a quality brake that is the best I have used.

Cool, I have been considering a brake.

After reading about more loads I realized a 140gr @3250 with little- no over pressure signs should be safe.

 

[tomt]

For what it is worth, Quick Load has Barnes bullets at a higher start pressure. 3626 psi for jacketed bullets and 4351 psi for copper bullets.

Tom