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#6328948 - 06/09/16 10:08 AM how much faster can you push it?
Big Stan Offline
Bird Dog

Registered: 05/02/14
Posts: 270

Following minimum and maximum loads is important when checking your powder charges in the reloading manual, most of us sticks to the minimum and maximum window, some of us, if you know what you are doing, like to push the bullet faster and keep tabs on the pressure signs such as sticky bolt lift, flat primers, split cases, etc. Reloading manuals have different charges / information and its where we make a decision " when to say Stop" and settle with a charge weight safely. As of today I found a tidy 3 shot group , .25 MOA, for my Sako lightweight 7 Mag with Shilen 26" barrel, used 140 Accubonds. Load was 66.7 grains of RL19 , lit with Fed215M and velocity is a strong 3240 fps with no pressure signs. The velocity reading was pretty high and how much more can you go? Does the sticky bolt / flat primers happen before the chamber even reaches maximum pressure? Just a thought and safety is priority one. Sometimes we tend to push it faster to see if there is a nice load for hunting which I like to do, but never have split a case or blew a primer before, ever in my 20 years of reloading.

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#6328974 - 06/09/16 10:36 AM Re: how much faster can you push it? [Re: Big Stan]
ChadTRG42 Online   happy
THF Trophy Hunter

Registered: 09/16/09
Posts: 9398
Loc: Lewisville, TX
If you look at the Nosler online data, your speeds are right in check with their data (3318 fps in a 24" barrel, compared to your 3240 fps in 26" barrel). Their listed max charge is 65.5 grains of R19 and yours is 66.7 grains (1.2 grains more). If you seat the bullet out further than the book 3.290", then that will reduce your pressures some and allow more powder in the case. The differences in lot to lot variation in R19 can also add in some variance. And not all chambers and barrels are the same, so there's a difference. And then with the "play it safe" Nosler load data, you can easily have an over book max powder charge and still be within a safe load. That's why tuning your ammo to YOUR rifle is the way to go!

http://www.nosler.com/nosler-load-data/7mm-remington-magnum/
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#6328987 - 06/09/16 10:44 AM Re: how much faster can you push it? [Re: Big Stan]
Jgraider Online   content
Bird Dog

Registered: 06/13/15
Posts: 263
Loc: West Texas
So you have a .25" group and you want more?

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#6329018 - 06/09/16 11:05 AM Re: how much faster can you push it? [Re: Big Stan]
papa45 Offline
Bird Dog

Registered: 05/14/07
Posts: 472
Loc: Arlington
Of course, there is no simple answer to this question. Most of us are not capable of measuring actual pressure. We can only look for signs that we think may be giving us some indication. I have loaded .243 Win over published max charges, only to find that my velocities start to decrease after some point, sometimes even before a published max charge. I have loaded .270 Win far over published max and the velocities just keep going up, with no signs of pressure. Was I building a bomb just waiting to explode? Maybe. Getting away with it once or 100 times doesn't preclude a catastrophe somewhere in the future. There are many factors, beside charge weight, that can influence pressure and its effects. A variation in any one of those factors could put you over the line...or not. Who knows?

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#6329145 - 06/09/16 01:00 PM Re: how much faster can you push it? [Re: Jgraider]
Big Stan Offline
Bird Dog

Registered: 05/02/14
Posts: 270
Originally Posted By: Jgraider
So you have a .25" group and you want more?


No, I stopped when I got the .25 group with 66.7 grains. I wanted to stop the charges at 66.5 grains, but made loads up to 66.9 to find a sweet spot. I am satisfied with the .25 MOA and not experimenting further except to make 30 rounds to sight in and to use for deer season. Just installed a NSX NightForce 8-32 on it last week. Took the off Leupold 30mm 6.5-20 LRT and having it up for sale.

It's just a question that bugged me yesterday when I was reluctant to go over 65.5 grains ( Nosler manual stated max load ).


Edited by Big Stan (06/09/16 01:03 PM)

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#6329150 - 06/09/16 01:01 PM Re: how much faster can you push it? [Re: Big Stan]
FiremanJG Offline
THF Celebrity

Registered: 12/16/08
Posts: 17893
Loc: Wolfe City, TX
Yes, I look for those signs, and have two rifles currently loaded waaaay over any published loads. They don't trash brass, and shoot very consistently. But when I am going above published Max, I ease. I put an asterisk next to that charge on the loading book, and carefully inspect brass after firing it. I don't push my luck, if I see signs.

.223 case I step in .2 gr increments

Standard short action I step in .3 gr increments.

Long action I step in .4 gr increments.

Lots of published Max loads are what I call "lawyer proof" thus very conservative. Berger gave me some load data that was way too conservative for the 7 Rem Mag, 180 VLD and Retumbo. My starting charge was their Max charge. I ended up at 71.2 gr, doing the load work-up in 100℉ in August. Good friend of mine built a rifle that is a copy of mine, same exact load recipe is where his shot best. And one THF member sent me a PM many months ago, that had also nearly copied the specs of my 7 Rem Mag. I told him my load, but told him to work into it, looking for pressure. As stated chambers are different, and powder lots are different. Fortunately, he did not see pressure signs, and yet again, landed on my load that shot great in his rifle.

But when my current barrel has to be replaced, I will continue to slowly work toward the "known" powder charge, again looking for pressure signs. Take nothing for granted.
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#6329162 - 06/09/16 01:09 PM Re: how much faster can you push it? [Re: FiremanJG]
Big Stan Offline
Bird Dog

Registered: 05/02/14
Posts: 270
Originally Posted By: FiremanJG
Lots of published Max loads are what I call "lawyer proof" thus very conservative. Berger gave me some load data that was way too conservative for the 7 Rem Mag, 180 VLD and Retumbo. My starting charge was their Max charge.


I assume you have a 1-8 twist to use the 180? Mine has the 1-9 and never tried anything over 168 grains. The 168 VLD I tried yesterday shot about .4 MOA with RL19 which is respectable accuracy.

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#6329175 - 06/09/16 01:17 PM Re: how much faster can you push it? [Re: ChadTRG42]
Big Stan Offline
Bird Dog

Registered: 05/02/14
Posts: 270
Originally Posted By: ChadTRG42
If you look at the Nosler online data, your speeds are right in check with their data (3318 fps in a 24" barrel, compared to your 3240 fps in 26" barrel). Their listed max charge is 65.5 grains of R19 and yours is 66.7 grains (1.2 grains more). If you seat the bullet out further than the book 3.290", then that will reduce your pressures some and allow more powder in the case.


The OAL length measured in the chamber is 3.324 with the AB and I believe I have it .015 off the lands. Won't be much to lengthen it, but I think jamming it in will raise pressure. The Berger Hunt 140 VLD shoots the exact same POI and groups .25 MOA as well with the same load as the AB. Haven't adjusted seating depths yet. Amazing.


Edited by Big Stan (06/09/16 01:19 PM)

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#6329215 - 06/09/16 01:42 PM Re: how much faster can you push it? [Re: Big Stan]
FiremanJG Offline
THF Celebrity

Registered: 12/16/08
Posts: 17893
Loc: Wolfe City, TX
Originally Posted By: Big Stan
Originally Posted By: FiremanJG
Lots of published Max loads are what I call "lawyer proof" thus very conservative. Berger gave me some load data that was way too conservative for the 7 Rem Mag, 180 VLD and Retumbo. My starting charge was their Max charge.


I assume you have a 1-8 twist to use the 180? Mine has the 1-9 and never tried anything over 168 grains. The 168 VLD I tried yesterday shot about .4 MOA with RL19 which is respectable accuracy.


Mine is 1:8.5" twist. I built the rifle to run that very bullet, and it does it superbly!

Berger shows a 1:9" will stabilize a 180 gr VLD, but I've not confirmed that.
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#6329303 - 06/09/16 03:00 PM Re: how much faster can you push it? [Re: Big Stan]
rrflyer Offline
Bird Dog

Registered: 10/19/09
Posts: 485
Loc: Denton---ish
The real question, to me, is why? What do you gain with an extra 50-75 fps? Especially on a hunting rifle at normal shot distances?

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#6329624 - 06/09/16 06:38 PM Re: how much faster can you push it? [Re: rrflyer]
Big Stan Offline
Bird Dog

Registered: 05/02/14
Posts: 270
Originally Posted By: rrflyer
The real question, to me, is why? What do you gain with an extra 50-75 fps? Especially on a hunting rifle at normal shot distances?

Nothing, but the gun would not shoot worth a darn until used the 66.7 grain load.

Sometimes you need to increase your velocity especially the Magnums to shoot well.

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#6329640 - 06/09/16 06:47 PM Re: how much faster can you push it? [Re: Big Stan]
noylj Offline
Light Foot

Registered: 12/08/10
Posts: 35
From the '50s to the early '80s, there were a bunch of Pet Loads from famous reloaders that many folks used.
Then, when those loads were tested using pressure transducers and such, it was found that many of those loads were 70-75ksi.
Back then, you loaded until the bolt was hard to life than backed down 0.5-1.0gn.
Thank God rifles were built STRONG.
You can PUSH things as much as you want, as long as you don't risk injuring any one else...

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#6330286 - 06/10/16 10:49 AM Re: how much faster can you push it? [Re: Big Stan]
Jgraider Online   content
Bird Dog

Registered: 06/13/15
Posts: 263
Loc: West Texas
Many times, especially with my 7mm Rem Mags the closer I would get to max pressure/high velocity for bullet weight, I found that accuracy would drastically increase.

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#6330420 - 06/10/16 12:48 PM Re: how much faster can you push it? [Re: Big Stan]
ChadTRG42 Online   happy
THF Trophy Hunter

Registered: 09/16/09
Posts: 9398
Loc: Lewisville, TX
Every belted case I have ever played with shot its best at max pressure.
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www.DallasReloads.com
Type 01 and Type 06 FFL

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#6330792 - 06/10/16 08:03 PM Re: how much faster can you push it? [Re: ChadTRG42]
FiremanJG Offline
THF Celebrity

Registered: 12/16/08
Posts: 17893
Loc: Wolfe City, TX
Originally Posted By: Jgraider
Many times, especially with my 7mm Rem Mags the closer I would get to max pressure/high velocity for bullet weight, I found that accuracy would drastically increase.


Originally Posted By: ChadTRG42
Every belted case I have ever played with shot its best at max pressure.


Yup, Yup!

I love feeling the powder crunch when seating a bullet.
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