26 replies to this topic

[novaman64]

So finally got some spare time with work slowing down (got a new job I start after turkey day) plus the rains put a dampener on my shop project, and with the addition of my new Lyman DPS 1200 Ive been reloading and developing some loads for a couple rifles. Lately have been concentrating on my Tikka T3 Lite 7 mag. Tried a couple different powders, but have had best results with H1000, I have been using my Berger 168 VLD's with a standard primer, and just cheapo Winchester brass.

Anyways, most accurate load I have had has been 68.5 grains of H1000... See pic...





Anyways, been doing ladder loads. Started down at 66 grains, most accurate was 68.5, when I hit 69-70 it start getting pretty wide (1"), and the most powder I have put through it so far is 71.0 grains of powder. Dont have any pressure signs yet, and the groups are starting to shrink back down (71.0 was at .632"). So should I keep going hotter to see if the groups get better, or leave it at 68.5 grains? Looks like most guys on soe other boards that are running the same bullets and powder are right around the 72 grain range getting between 2900-3000 FPS...

Out of a 24" barrel how much velocity is an extra 5 grains of powder going to give me?

[Frank]

This is one of those often repeated (good) questions on many forums regarding handloading. Anyway...

Started down at 66 grains, most accurate was 68.5, when I hit 69-70 it start getting pretty wide (1"), and the most powder I have put through it so far is 71.0 grains of powder. Dont have any pressure signs yet, and the groups are starting to shrink back down (71.0 was at .632").

Yep, situation normal... In other words, often times, but not always, the "mid" range load (your 69-70) can be the least accurate and why many folks, especially beginners, quickly go back to their starting loads (instead of moving forward / upward) & thus settlle with lower velocity than what a given caliber is capable of. EI: Obtaining only 223 speeds in a 22-250 caliber. A VERY common error! Why pay more for the expensive (250) components if shooting at 223 levels? Just buy a 223 then.

Out of a 24" barrel how much velocity is an extra 5 grains of powder going to give me?

That is anyone's GUESS... Remember, ANY reloading manual is only a guideline in terms of powder charge and velocity, and should not be taken as Gospel, as each rifle is different... even by the same brand. Remington etc! Only a chronograph can tell you.

However, with that said, my "GUESS" will be in the 200 fps range (+/-). And again, the actual speed can be MUCH higher or lower (than my guess).

Anyway, sounds like you're doing fine, and good luck.

p.s. I really am old. I always used a "ladder" for "house" work, not handloading. Do these ladder loads go with a "walking" rifle too? I always "walked" a dog & carried my rifle. I can't help myself. I just can't keep up with all this new high tech stuff / lingo

[tawnoper]

If I may so humbly suggest...if you're getting "consistent" 5/8" groups out of a stock 7mm Rem whatever, I'd call it good. Doubt you'll improve much on that.

By the sounds of it I don't think you're doing "ladder" loads. Sounds like you are loading up a few at 66, 67, 68gr etc. shooting them and registering the results.

As for barrel length, depending on which powder you are running you'll get to a point where more powder doesn't equate to much.

[Kephers]

5/8 groups are pretty good. Settle with that round and maybe try playing with seating depth a little.

[Bisley]

Half the battle is already done, at the end of the day you have a load you know shoots great, so would do you possibly have to lose if you see if you can the same potential with a bit more speed? Even if it doesn't work out for the better you will not have that question in the back of your head every time out. And that can be a big thing, especially in sport so mentally involved like shooting/hunting. You have nothing to lose and only something to gain as you already have a go-to as it is.

[sxshooter]

I've seen this situation in loading for my rifles. You see the same phenomenae in the BOSS equipped rifles. But with a BOSS, you change the natural frequency of the barrel by either lowering the frequency by lengthening the barrel or increasing the frequency by shortening it. The goal is to get the bullet to exit the barrel when it's moving the slowest or actually stopped and the end of it's whipping motion. With changing velocity by changing the charge, you change when the bullet exits the barrel. The most accurate load will be when the barrel is at the end of a whipping cycle when the bullet exits the barrel...same as adjusting the BOSS. If you load low enough, you catch one of the cycles, and then another if you load high enough.

[Frank]

Half the battle is already done, at the end of the day you have a load you know shoots great, so would do you possibly have to lose if you see if you can the same potential with a bit more speed? Even if it doesn't work out for the better you will not have that question in the back of your head every time out. And that can be a big thing, especially in sport so mentally involved like shooting/hunting. You have nothing to lose and only something to gain as you already have a go-to as it is.

If you load low enough, you catch one of the cycles, and then another if you load high enough.

BINGO... (on both above)!!

Also 5/8" with how many shots? (I can't tell on the target). If 5 shots, then most excellent indeed... If 3 shots, then it is more than decent for sure, especially for a stock rifle used on coyotes. However, 3 shots in 5/8" is not a spectacular "predator / varmint" load. Any varmint rifle, load & shooter worth their salt can put 3 rounds into roughly 1/8-1/2" groups at 100 yards all day long.

So yes, he has a good load indeed... but why not at least "attempt" to make it a GREAT load... if possible??

[novaman64]

3 shots into .493" was my most accurate, thats including the cold bore. 2 of the shots were .166" apart, want to try and bed the stock to see if that helps bring the cold bore in...

[Frank]

I screwed up... AGAIN

I forgot we were talking about a 7mm mag that is more likely used for medium to large game. So most everything I said would still apply, except for the itty bitty 1/8-1/2", 3 shot size groups. The groups would typically be larger from a stock 7 mag in other words. UGH, I really am losing it.

[Braz]

I am not a big fan of chasing the speed. All it does if cost you more money. In powder and barrels when you burn them up. Get a good group an call it good is my feeling.

[Desert Fox]

Have you chronograph this load. If so what's the velocity you're getting.

[novaman64]

I dont have a chrony... So no...

I just joined the El Dorado Rod and Gun Club, everyone is super nice, need to talk to some members and see if someone has one...

[sxshooter]

The 7 Mag is similar to a long favorite of mine, the .264 Win Mag. Both share exactly the same case dimensions except for the neck diameter. Both are fast and flat shooters. But with a heavy bullet, a hunter that reloads either is always seeking speed.

I have run into problems loading up to what I thought was the limit. It happened on some .264 loads, 7 Mag, and '06 loads over the years. The first time it happened was in '76 when I loaded some 150gr '06 load. I thought I had backed off enough from pressure signs. Evidently not. The cases were sticking. Fortunately, I had another rifle with a different load with me to save that hunt in Colorado. With the mags, the case usually sticks just above the belt.

At the range, I was cleaning the bore often and the chamber was getting coated in solvent and only a few rounds fired then cleaned again. I learned to degrease the chamber and bore when reading case pressure signs. No problems since.

[Desert Fox]

71 grain is almost max for that load. I don't think you need to go further without knowing exactly what kind of velocity you're getting. Some hot loads won't show the normal tell tail sign until it's too late.

Chronograph is very affordable this day. It is the most important tool every hand loader must have.

[sxshooter]

Another highly valuable tool is a Pressure Trace. I bought one about 7-8 years ago. No more guessing on pressure.

[tawnoper]

I dont have a chrony... So no...

I just joined the El Dorado Rod and Gun Club, everyone is super nice, need to talk to some members and see if someone has one...

I'd imagine for the price of one years membership to a gun club (50-75 dollars?) you could buy a decent chronograph and have it forever.

I'm not discounting the use of a strain gauge...but that's quite an investment for a hobby shooter. Unless I was developing some new cartridge with no info available I couldn't see myself using one much. There are lots of nice tools out there if you want to spend the moola. I'd like to have a nice bore scope.

[sxshooter]

I was doing load development for 100 year old damascus shotguns and wanted more than a loading manual reference to pressures. That was my reason for getting a strain gage system...that and engineers always want more data.

[Frank]

that and engineers always want more data.

I KNEW IT !!

[sxshooter]

It's an affliction Frank. A little sympathy here please.

[Frank]

I completely understand... having a few family members & friends as engineers and all

[tawnoper]

Union Pacific or Tyco?

[Frank]

both

[sxshooter]

Frank,
My wife is a mechanical engineer and has a math degree as well. That math degree got her the job of balancing our checking account.

Still, she hates watching movies with me when I start saying something about the technical inaccuracies, etc.. I just don't understand why...

[True2ThySelf]

Still, she hates watching movies with me when I start saying something about the technical inaccuracies, etc.. I just don't understand why...

My wife pokes fun at me for doing the same thing!

[sxshooter]

I gotta run home and wrap her Mini Pad (ipad that is) for her early celebration of her Bday. I figured out how get her to go to dinner tonight to celebrate her Bday so I can go hunting on her real Bday, which is Saturday. Is that a great wife or what?

[novaman64]

I never was able to master that one with and of the women I had gone out with. My 3 year relationship about ended when I missed our anniversary and went deer hunting. oops...

Thanks for all the info guys, I am going to look into pickup up a chronograph...

[sxshooter]

I like to think 30 years together buys me some slack. I'm pretty sure it's just all in my mind.