To crimp or not to crimp 7MM Rem Mag.

Greetings all, I just reloaded my first nine boolits for the aforementioned 7MM.
The boolits I used are as follows Nosler 150 Grn Ballistic Tip Spitzer.These do not
have a crimp groove. They measure1.307 now 0.515 is going into the neck for an
OAL of 3.286 The Max OAL is 3.290 My case lenght is 2.496 . I hopes the figures help.
I know their are more experianced loaders out their for this caliber. I started my ladder
with the minimum load of 59.0 Grns IMR 4350.Any tips will be appreciated.
Thanks .

I just love the 7 mag its a great round. IMR4350 is a great powder too. there are others a little slower that you may want to consider if you dont get the results you are looking for. as far as OAL as long as it will feed in your rifle I.E. in and out of the magazine its ok. The Case OAL is some what critical as you dont want the the case neck in the throat of your rifle you want it to be able to let go of the bullet. You need to crimp at least a little if you plan on hunting with the rifle. Other wise recoil will move your bullets. If your bullets dont have a crimp grove I would consider the Lee FCD. Yea I know I am not known for being a lee fan but the factory crimp die is a lot better than trying to roll crimp into nothing.
Bench rest shooters back in my day didnt crimp at all and they were shooting one hole groups at 500 yds so I reckon they knew a little. But they were loading one at a time.

I may be wrong , but I like to put a light crimp on most anything I load using the Lee factory crimp die. I guess I feel like it keeps them from moving too much under recoil and maybe have a more consistant point at where it leaves the case. Just my opinion - -

i agree with both replys above.. unless your going to load one at a time, its better to taper crimp them a little at least....bill

Thanks guys, I just finished another round and put a slight crimp on all
of them. Now I am gonna work up some with IMR4064 which is a faster powder.I hope I can get to the range at some point.I used magnum large
rifle primers with the slower burning IMR4350, Thats what the book recomended. However did not specify for the faster powders. I should still
be able to use the magnum primers and back off load. Or just use regular
large rifle primers with the IMR 4064.What say yall? And thanks again.

I never crimp my 7mag rounds so let me know how it turns out.

I am sure that the 7mm mag has more ooomph than my 270. Being a bolt action, I don't crimp any of my 270. I soon hopefully one day will have a 7mm mag myself, not holding my breath, so I will have to see how things go with this...

My old Ruger 77 tang safety was pretty beat up, when it was in its original caliber of 7mm Rem Mag I did not crimp the rounds and had no issues with cartridge set back.

I left some Combined Tech 175gr in the bottom of the mag well for a total of 20 full house loads 72.5gr of Retumbo and had no issues with cartridge set back but the nose of the bullet was buggered up a bit from slamming into the front of the mag well.

Last year I sent the old Ruger 77 off to Shilen for a new 30" Palma-weight barrel in 7mm STW and a touch up on the action.

Rifle was knocking the crap out of me shooting my favorite 175 Combined Tech bullets, so I sent it to E Arthur Brown for a howitzer-style muzzle break and a hard satin chrome finish.

I have not noticed a marked difference between crimping bullets or not in accuracy, but I mostly use Retumbo or Ram Shot Magnum in the 7mm STW.

I would crimp a few of them and see if it shoots better

Johnny, most usually I don't crimp my rifle rounds at all, but lately I have started using a real light crimp. Not so much because I'm afraid of the bullet getting moved or falling out, but more so to build up the pressures that I need.
I don't think the casing was building up full pressure before the bullet was already on it's way down the tube. Which I think hurt my velocity as well as my accuracy? So I started putting a light crimp on my rifle rounds just to snug the neck around the bullet ever so slightly.

You'll just have to play it by ear on this one because all calibers are different, some don't mind a crimp and others don't like it at all. It can even vary from one gun to another.

Try some with and some without and see how your rifle likes the crimp, but I doubt there will be a noticeable difference in accuracy if you want to put a light crimp on your rounds.

Like Mo said I too vary my crimping per rifle.

Take careful notes while you are at the loading bench and the range. Detail how much crimp you put on the rounds (or not) and then how those rounds shot.

I am admitidaly (sp?) anal about my record keeping both on the loading bench and the shooting bench, so I have piles of paper detailing my loads, groups, and other such BS as weather, geography, etc.

My .300 WSM loves a heavy crimp and groups better and has less fouling. My Browning .30-06 hates crimps other than a light one to snug the bullet in the case. My Argentina M98 .25-06 AI hates crimps at all.

I have heard theory that a crimp lets pressure build and the powder to burn more completely, but not sure if that is urban legend or not.

Richard Lee swears by crimping. Hence his factory crimp die. I used to shoot at the bench rest rifle club a little west of wright city, Mo. The guys who live and die by bench rest competition swear by no crimp at all, and these Ladies and Gentlemen consistently put one bullet after another inside the same hole at 500+ yards. I think they kinda know what they are doing. Me however I'm just an old sailor and hunter target shooter for fun and practice. Since most of my shooting is for hunting and I'm more worried about minuet of Varmint. I look at crimping more as insurance than accuracy. If I load up a bunch of hunting rounds and say go to Alaska or Montana for a moose hunt of a life time and loose half or more of my ammo because the bullets either fall out of the case or get pushed into the case all the way... hasn't happened on a hunting trip but has on my 223 here at the farm. So I personally crimp for that reason alone. Most likely you would have enough neck tension that it will hold your bullets secure enough but I wont take that risk.

I tend to crimp all my military calibers especially anything that is magazine fed.

I too try to keep my bullets in minute-of-prarie rat (AKA self-erecting biodegradable target), but I strive for the best accuracy I can get although many of my rifles shoot much better than I do.

My big belted magnums all get a decent crimp more to hold the bullet against set back from recoil than any desire for accuracy improvement.

If I ever make it back to Alaska to chase moose and caribou again, I damn sure will make all my bullets crimped tight to ensure recoil does not mar a cartridge and ruin the shot of a long dreamed of hunt.

I only crimp for my semi auto's.....