Duplicating factory 7mm magnum

[odsixer]

Anyone do this? I'm going to make some 7mm remington magnum for my Dad and one of his buddies. I have some 130gr accubonds and wondering if anyone has factory load data I could use instead of working up a load for both rifles.

Thanks.

[Sevens]

In almost every case, there really is no such thing as "factory load data" because the powder that most factories use is a proprietary blend. The best you can typically do is find in print what velocity they attain and try to match it or best it. And remember that a published "velocity" from factory ammo isn't necessarily what any end user will absolutely guarantee to get in his own rifle.

To do the best you possibly can, you'll need a chronograph and measure what you get from factory ammo. Then, using a different selection of powders, start to approach that.

But the powder is key... Nobody has that powder for sale. You have to try to match the factory load with the powder choices we do have.

[odsixer]

Thanks, that's a good start.

[ForneyRider]

Didn't know you can get 130gr for 7mm Magnum in factory ammo to match.

In Rem. 7mm Mag, 140, 150, 160 and 175 are common, with Hornday's 139gr, 154gr, and 162gr thrown in.

I like the Federal 215M primer for this round. But have used the WLRM, and CCI 250.

I have 120gr Nosler Ballistic Tips, 139gr Hornady SST, and 162gr Hornady Interlocks. The Interlocks will be my first 160 grainer. There are better target bullets at 160-168gr, but I thought these were a deal for 24$/100.

I am using Reloder 19, Reloder 22, Reloder 25, and IMR 4350.
Reloder 19 and 22 should cover anything in 7mm Magnum except for maybe 175gr(Several makes) or 180gr(Berger) bullets. I got the Reloder 25, but may not need it. It is for ultra mag rifles with heavy bullets, a very slow powder.

Nosler's sight has some nice loads that are plenty stout. Some exceed factory velocities. I use their book for a lot of my loads with excellent results.

Most of the ammo manufacturers have the velocity of the ammo as well as other properties. You can try matching them with a powder offered to reloaders. Some show the primer used, like Remington.

[Ulrice]

ForneyRider, I have loaded my 7mm Rem. Mag. with the 162gr. spbt bullets using RL25. The results: spray and pray. It didn't go well no matter what I did. I have used RL19 and RL22 with the 154gr. sp bullets with pretty good performance.

[thekyrifleman]

I've reloaded the 7Mag for over 40 years. Used H4831 and 140 gr Sierras. Killed everything I shot at, and was very accurate. Don't expect to get the velocities the manuals state. With lierally a case full of H4831, the best velocity I could get was an even 3000fps. Tested that many, many times. About 10 yrs ago tried RL19 with 140 Nosler BT and matched the Remington factory loads at 3050fps. Killed a nice caribou with that load. This is with a 1965 Rem 700 with the original 24" stainless barrel...they don't make them anymore. If you look at the new Nosler manual, they say 3300+ with the same RL 19 load. Don't know how they do it....that's more like the STW speeds...I have one of those also...got it built on a 700 action..right out the Shooting Times article by Layne Simpson, backin the late 80's. Got 3425 with H1000..sweet....

[ForneyRider]

My Nosler book has loads for 7mm Mag with 160gr bullets at ~3000fps. Most, if not all, of published test data are the results of using test barrels, not real guns.
Ceteris paribus, test barrel > single shot > bolt action > semi-auto/pump.

Nosler's website has loads, but the book is great for learning the history of each cartridge. Ken Waters wrote the page on 7-30 Waters, Col. Jeff Cooper wrote the 10mm and 45ACP pages.

The Reloder 19(light bullets) and Reloder 22(heavy bullets) should cover anything in Rem. 7mm Mag with top performance. IMR 4350, IMR 4831 should do the same from IMR. And H4350 and H1000 for Hodgdon. Only thing I've used of Hodgdon is H110 and Varget. All are excellent powders in their own right.

I enjoy testing different powders, but looks like the Reloder 25 may be on the shelf for a while. At least until someone I know gets an Ultra Mag.

I am still bargain shopping for a chronograph. The Shooting Chrony Beta looks pretty good.

A 120gr Varmint bullet in 7mm Mag has pretty close to same trajectory as a 50gr .22-250. But the .22-250 has a lot less kick, and uses a lot less powder.

[T. O'Heir]

"...get 130gr for 7mm Magnum in factory ammo..." You can't according to Midway's list and Remington's site. Even if you could get factory 130 grain ammo, you'd still have to work up a load for each rifle. Or try a box of as many brands as you can to find the ammo each rifle shoots best.
My Lyman book gives IMR4064 for the accuracy load using a 130 grain jacketed bullet. 53.0(2914fps) to 59.5(3185fps). No factory duplication load for any bullet weight but 175's. Mind you, it's not the most recent manual.

[odsixer]

Sorry Guys, I meant to say 160gr ( I think I had .270 in my head). I have 160gr accubonds.

Forney, the nosler book sounds good, I currently have the speers and lyman manual only.

It's of course impossible to work up a load with out having the rifle so I'll try to get close to 3000fps, then have my dad shoot a couple of groups with it and go from there. I don't think he needs sniper accuracy but minute of deer would be nice;'

Thanks again for the info.

[ForneyRider]

I took another look at the Nosler book this weekend. They have a 1:9 twist 23.5in test barrel for 7mm mag data. They don't list the OAL.

My 7mm mag is ~26in with 1:9.5in twist. I measured the length, but looked up the twist online.

I did some 120gr Nosler Ballistic Tips, 139gr Hornady SST, and 162gr Interlocks. The Interlocks have a lead tip, the others are plastic.
Using Reloader 19 and 22 on these with Federal 215M primers. Using the load data from Nosler.

I am not using the cannelure on the Hornady bullets. The Nosler doesn't have a cannelure. I made the OAL as long as I could and still fit in magazine and chamber.

Out of 7 hunters, we had 3-4 guys shooting factory 140gr and 150gr 7mm mag ammo at East Texas white tail deer.

My Chrony is being shipped. I'll post fps when I can get back to the range.

[ForneyRider]

Oh yeah, these are neck-sized.

The ones I made for some of the other guys are full-length sized and bullet seated to where the mouth swallows the cannelure with no roll crimp. I don't have a roll crimp die.

[odsixer]

Thanks Forney, great info.

[ForneyRider]

IMR7828 was a factory powder for 7mm Magnum made available to reloaders.

I think there is a short cut version of it now.

[ForneyRider]

MAX LOAD WARNING!

I ran 68gr of R25 and the 162gr Interlock and came up with 2700fps. I didn't have a scope on so I just made 3 shots to get an average FPS. These were neck-sized and the bullet was not set very deeply, so I think my velocity was down about 200fps from where it should have been. I may actually go over maximum. I am thinking with a case as large as the 7mm Mag, that the pressure differences between neck-size and full length-size is significant.

Never shot this rifle without a scope. My groups were fist sized at 100 yards. Not bad I thought.

[a7mmnut]

I've used 4350, RL 19 and 22, 7828 and H1000. 130's are a little too light in the mag. I load the Speer 130's in my 7-30 Waters and 7mm-08--both with Win. 748. In most of my Rem. Mag. loads, H4831 is the way to go. Put 62-65 grs. under the 150's or 160's, and you should find a sweet load. I can easily beat factory velocity (2950) with the 162 Hornady or Sierra 165 in my 26" Winchester, but never came close in my old 24" Ruger, which loved the 150's (3110). IMHO, 2900 is moving just right. -7-

[El Paso Joe]

Ditto on seven's approach.

I will chronograph a box (20) of whatever I want to duplicate. Caveat: The chronograph results will probably be different than the published performance of the factory loads. Then I will start with a powder that will have the chronographed velocity in its range and work up until the average for 20 handloads is the same as the average for the chronographed factory loads. I check the standard deviations to see how large it is (sometimes it is scary...) and if it is not too bad I will go with the load.

Good luck.

[a7mmnut]

Joe's got a good point. When starting at "ground zero", I load my best guess starting load with each bullet choice in 2 rounds, then increase or decrease .5 gr. in every two rounds for a complete box. I then switch powder or bullets and make another 20, pairing them in the same manner. Same for my OAL adjustments. Shooting every two rounds through a chrony will show you what to expect in terms of accuracy. Once I get over 15-20 fps in deviation, I stop right there and switch primers or powder. This is a personal choice, but has saved me plenty of components in the past. I've found that the most accurate loads will be within that tolerance range for even just two rounds. I also like to use neck sizing only to save strength at the belt, use powdered graphite on the necks for seating, and light the slower powders off with the Federal 215's. Good luck. -7-

[ForneyRider]

I picked up the Lyman 49th. They like H4831 powder for 7mm Mag.

Their loads are right with factory loads even the Hornady Heavy Magnum, which runs about 100fps faster rated than typical.

I did use the R25 for some 168gr SMK's but got no better accuracy than Hornady/Nosler hunting bullets 120gr-162gr with R22. The Accubond is excellent. My brother's 8x57 shoots better with Accubond than SMK as well.

I am still experimenting, the next batch has groups of 10 with different primers. After I find the best primer, I will experiment with OAL.

[Doodlebugger45]

Trying to "duplicate" a factory load isn't ne velocity isn't necessarily a good thing to do. You can usually match the velocity or even exceed it but it might not shoot very well. And the factory ammo might not shoot all that well either in your particular rifle. With a cartridge like a 7 Mag, you will have plenty of velocity no matter what load you use. You should strive for accuracy not velocity. For all my elk or deer cartridges, I would gladly take one moving at 2800 fps that gives me less than an inch group at 100 yards over an equivalent round that moves out at 3000 fps but only gives me 2.5" groups. If you think the difference in accuracy isn't important, just remember what the likely error will be when multiplied by 3 or 4 if you take a long shot at an elk.

[GeauxTide]

Rem 700, 24" barrel, maximum loads in my rifles (.005 Case Head Expansion).

140 Nosler BT - 3179
145 Speer - 3130
150 Nosler BT - 3069
154 Hornady - 3007

H-4831 gave better Standard Deviation and Extreme Spread results than IMR-7828, and H870.

I've found standard bullets 150 and under at over 3000fps hit 150# deer like bombs and make a mess.

[James R. Burke]

I worked up a load for a friend using IMR-4831 with Nosler 150 grain b.t. that worked great. If I was to do it over I would go with the partitions.