7mm Mag help

[PHOENIX PHIL]

Glad you made it home, saw this on the news. At some point, I hope the world wakes up.

 

[Bullthrower338]

When it comes down to Defending our selves and families, the left can use their political correctness and I will count on my 1911 that is on my right hip!

 

[lcq]

When it comes down to Defending our selves and families, the left can use their political correctness and I will count on my 1911 that is on my right hip!

You are fortunate, no carry here. Up here in the socialist workers paradise it is you who gets arrested for defending yourself with a gun then the police take all your guns and revoke your license. Never ever allow the leftists to corrupt your constitution or limit your freedoms. The world is full of examples of where that ultimately leads.

 

[lcq]

Glad you made it home, saw this on the news. At some point, I hope the world wakes up.

Frankly I am afraid of what you have inhabiting the White House today and while our current government is common sense the radical socialists waiting in the wings scare me to death. Who knows I may just be looking for a country with its head screwed on straight if the Liberals win the next election.

 

[JGRaider]

I've been shooting and loading the 7mag for years. I've found that my 7mags have always responded well (load accuracy increases) at or very near max pressures. With that in mind, and the usual "work up in your rifles), 71.5g Retumbo gets me 3075, and 66.5g RL22 gets me 3030 in another rifle. All with Fed 215M primers. Of the powders you mentioned, I'd grab the 7828 first.

 

[Warbird782]

I have not seen a 7mm Rem yet not shoot well with 7828ssc with 160's or 168's.

 

[lcq]

just back from the range and 66.2gr ( 65.7 book max) W-780 gets sub moa at 2900 slightly flat primers but they are soft Winchester, no real pressure signs.

Next up 7828 I managed to find a pound.

Nosler and Hodgdon both claim 64gr max at 3015 and 2868 we will see what I get next week.

 

[PHOENIX PHIL]

Well you in the ballpark now.

 

[sestoppelman]

just back from the range and 66.2gr ( 65.7 book max) W-780 gets sub moa at 2900 slightly flat primers but they are soft Winchester, no real pressure signs.

Next up 7828 I managed to find a pound.

Nosler and Hodgdon both claim 64gr max at 3015 and 2868 we will see what I get next week.

Well at least you are now up to .280 Rem speeds. And yeah, Win primers do flatten quicker than others. CCI seem to be the most resistant to flattening, at least in my use.

I have had great luck with Win cases though over the years, as Phil says, they usually hold a bit more powder and I don't have issues with them. I have a nice old M1 Garand that I use Win cases in and have for 20 years. The rims get all beat up and the chamber marks stack up on the last set of marks, but by golly I have never had a case fail in any way in this rifle and I usually throw the brass away after a dozen or so loadings, mostly because of the rim battering and overall appearance. The M1 is not easy on brass but Win holds up well. Ran into the same thing with an M1A when I first starting shooting one in NRA matches. Had been using Rem cases and was only getting max, 3 loadings out of them before a bright ring would show up. Several shooters said, switch to Win cases. I did and at least doubled my case life. The M1A is probably harder on cases than the Garand.

 

[Warbird782]

Here is some of my load data. 168 Berger loaded with 66.9 grains of IMR 7828ssc. Please do not start there as this is above book max. COAL is 3.452. I pulled some of the Bergers to load 160 Accubonds for Africa. They had a COAL of 3.353 and shot gang busters accurate. My PH had stated that he never had a client put 3 into one small hole at 100 yards like I did off of an unsteady rest. The velocity I am getting with the Bergers is 3053 with a 26'' bbl. I did not chrono the AB's.

 

[lcq]

Here is some of my load data. 168 Berger loaded with 66.9 grains of IMR 7828ssc. Please do not start there as this is above book max. COAL is 3.452. I pulled some of the Bergers to load 160 Accubonds for Africa. They had a COAL of 3.353 and shot gang busters accurate. My PH had stated that he never had a client put 3 into one small hole at 100 yards like I did off of an unsteady rest. The velocity I am getting with the Bergers is 3053 with a 26'' bbl. I did not chrono the AB's.

I got the plain Jane 7828 ssc not available. It has density 5% less than 780 so it will fill the case better. I'll wait till next week. Nice thing about retirement is I don't battle the weekend crowds.

BTW max OAL for reliable feeding gets me 25 thou from the lands

 

[lcq]

Here is some of my load data. 168 Berger loaded with 66.9 grains of IMR 7828ssc. Please do not start there as this is above book max. COAL is 3.452. I pulled some of the Bergers to load 160 Accubonds for Africa. They had a COAL of 3.353 and shot gang busters accurate. My PH had stated that he never had a client put 3 into one small hole at 100 yards like I did off of an unsteady rest. The velocity I am getting with the Bergers is 3053 with a 26'' bbl. I did not chrono the AB's.

Well I wonder what Nosler is smoking to get 3008 out of 64gr IMR7828 because at 63 I got 2700 and the cases were smoked at 64.5 2803 and not even a flattened primer. By my back of the envelope calculation I will be close to your 66.9gr to squeak out 2900. so far it looks more promising for the W-780

 

[JGRaider]

I'm sure you understand that book velocities are often times measured with special 26", match grade barrels, or some sort of special barrel. That W780 is very close to the burn rate of my favorite 7mag powder, RL22. You should be able to work up to 65.5-66.5g of W780, but obviously do so cautiously.

What is your COAL?

 

[lcq]

I'm sure you understand that book velocities are often times measured with special 26", match grade barrels, or some sort of special barrel. That W780 is very close to the burn rate of my favorite 7mag powder, RL22. You should be able to work up to 65.5-66.5g of W780, but obviously do so cautiously.

What is your COAL?

OAL 3.342 (25 thou from lands) Nosler claim to be using a 24" barrel same as mine but they are seating to SAAMI 2.9. I like to seat long an old habit from my IPSC days

 

[JGRaider]

Not sure what's up with the smoked brass. I've found that most of my most accurate loads in my 7mags seem to come at, or near max pressures. Are you sure your chrono is working correctly (just a thought)?

 

[lcq]

Not sure what's up with the smoked brass. I've found that most of my most accurate loads in my 7mags seem to come at, or near max pressures. Are you sure your chrono is working correctly (just a thought)?

Soot to me means the pressures are too low. That would square with your experience of the 7mm liking to be run hard. I just may have to put a bit of a crimp to allow pressure to build if nothing else works

BTW I checked with factory ammo and the chrono is on.

 

[Gerard]

lcq,

Differences between rifles chambered for the same cartridge sometimes play havoc with published loads and speeds. I have seen where start loads gave maximum pressure/speed and, in a different rifle of the same cartridge, where charge loads above the highest published maximum load gave similar pressure/speed. Speed at maximum pressure in the two rifles were very similar. These are extreme situations but they do happen.

The common factor here is speed and not charge weight. Load and pressure do not always go together and a more reliable way to estimate the pressure is by measuring the speed, which you are doing.

The signs of pressure and the signs of headspace are also very similar and the only way to tell tell them apart easily, is by measuring speed. Headspace can be a condition of the rifle and this is uncommon. It can also be a condition caused by tolerance stackup in the loading process that is caused by method and the various components that are used.

To work through the situation that you are experiencing, there are a couple of steps I would take:

# Set up the sizer die according to these guidelines. Follow the recipe step by step, there is method in the madness and the setup takes care of headspace, regardless of whether it is caused within the reloading or the rifle.

http://www.gsgroup.co.za/faqsizerdie.html

# Work up the load, paying no heed to charge levels, only the speed that you get. The caveat here is that you must be sure that the chronograph is reliable and that you watch for signs of pressure.

Let us know what happens.

 

[lcq]

lcq,

Differences between rifles chambered for the same cartridge sometimes play havoc with published loads and speeds. I have seen where start loads gave maximum pressure/speed and, in a different rifle of the same cartridge, where charge loads above the highest published maximum load gave similar pressure/speed. Speed at maximum pressure in the two rifles were very similar. These are extreme situations but they do happen.

The common factor here is speed and not charge weight. Load and pressure do not always go together and a more reliable way to estimate the pressure is by measuring the speed, which you are doing.

The signs of pressure and the signs of headspace are also very similar and the only way to tell tell them apart easily, is by measuring speed. Headspace can be a condition of the rifle and this is uncommon. It can also be a condition caused by tolerance stackup in the loading process that is caused by method and the various components that are used.

To work through the situation that you are experiencing, there are a couple of steps I would take:

# Set up the sizer die according to these guidelines. Follow the recipe step by step, there is method in the madness and the setup takes care of headspace, regardless of whether it is caused within the reloading or the rifle.

http://www.gsgroup.co.za/faqsizerdie.html

# Work up the load, paying no heed to charge levels, only the speed that you get. The caveat here is that you must be sure that the chronograph is reliable and that you watch for signs of pressure.

Let us know what happens.

Thanks for the tips, they explain a great deal. I just bought a neck sizer which correct me if I'm wrong is what you are doing with the masking tape and a FL die. I'm in the middle of deer season so development will be on hold for 2 weeks. I'll let everyone know how things progress.

 

[JTEX]

My 7mm RM is mo go to rifle. I stumpled on a load using RE19 with 168g Bergers that shoots lights out. It chronies and dopes out at 2990fps and shoots considerable less than MOA out to 800 yards. The case is no where near full cause I stick the bullets way out to touch the lands, luckily they still fit the magazine. I have tried my loads in several different rifles and only one has shot what I would call badly. No it ain't a magic load but it seems to work pretty well for that caliber.

 

[lcq]

My 7mm RM is mo go to rifle. I stumpled on a load using RE19 with 168g Bergers that shoots lights out. It chronies and dopes out at 2990fps and shoots considerable less than MOA out to 800 yards. The case is no where near full cause I stick the bullets way out to touch the lands, luckily they still fit the magazine. I have tried my loads in several different rifles and only one has shot what I would call badly. No it ain't a magic load but it seems to work pretty well for that caliber.

I'm lucky enough that this what I would call a disposable rifle shoots very well (0.474 3 shot 150gr core-lokt) for what it is. It also gets me 25 thou from the lands at mag length, something I can't dream of with my Tikka or Savage. Powder is like gold and more scarce up here so RL anything is a non starter. I love Bergers for varmints but wouldn't use one on a game animal, just too frangible and picking lead fragments out of my teeth doesn't appeal to me. If the weather co-operates I may make it out to the range before it snows.