Gentlemen,

I finally got to try out my new chronograph...

Naturally, the first things I had to try were my published maximum loads that I had loaded....most weren't even close to the published velocity

1) 7mm RM, 175 gr. Nosler Partition, Max published load 62.5 gr. Reloader 22, Fed 215 primer PUBLISHED VELOCITY 2970 FPS

Ruger M77 MkII 24" Barrel
ACTUAL VELOCITY - 2744 FPS (5-shot average)

2.) 7mm RM, 175 gr. Speer GS, Max published load of 61 gr. Reloader 22. PUBLISHED VELOCITY 2834 FPS
ACTUAL VELOCITY - 2740 FPS (5-shot average)

I know they get the velocities in pressure barrels, but that leads me wondering what I should do to get more velocity

Joel Slate
Slate & Associates, LLC
The Safari Specialists
www.slatesafaris.com

7mm Rem Mag Page www.slatesafaris.com/7mm.htm

I am getting slightly higher velocities with 175's and IMR7828 in my .280 Rem!

Nothing like a chrono to burst ones bubble. NOW you'll really learn something about handloading.

I have had both "fast" and "slow" barrels. Sometimes thats just the way it goes. But I have generally found that most manuals are pretty conservative. I seldom go for the MAX loads anyway but you do occasionally get a rifle that shoots better the hotter the load goes. At least to a point.

FN

Joel,

Some of my friends here might disagree with me on this one.

I use a chronograph as an indicator for the velocities I might get in one particular rifle, not as a rule to say that X grains of powder will give you Y velocity in such and such a caliber.

We probably shoot more than most who frequent these forums, and one thing we have learnt is the very little consistency in velocities between different rifles with the same caliber.

The velocity difference can be very small, or very large.

A change of any componet, like different lots of the same powder, can make quite a difference too.

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saeed@ emirates.net.ae

www.accuratereloading.com

jr,
i'm new with the reloading, but have had the chrono, and it's almost depressing... but i've noticed that little things have alot to do with velocity, as stated above. some primers get as much 6% higher velocities. temperature seems to be a big one here in MT, and those are just the beginning. the guys on this site can learn us the ways. good luck with your loads, and keep any info coming. nate

Check the fine print on those published velocities...more often than not, they're achieved with a specific tailored load and a longer barrel than comes on many rifles.

Prime example: the Lazzeroni published figure for their cartridges. The numbers dazzle the eye, until you consider they're achieved with 26 inch barrels, and that their rifles often come with 22-24 inch barrels - meaning you couldn't come close to published speeds even with their factory ammo. Of course, they publish the usual disclaimer - but it's all in the fine print.

I've noticed the same thing with some reloading data - the velocities published come with 24-26 inch barrels, where the average game rifle for that caliber may have a 22-24 inch barrel. Some manuals and sources are starting to go more towards using test barrels reflecting the rifles most likely to use the data, but not all do.

TXLoader

I've found published velocities to be fairly close to my tested velocities, when factoring in a velocity loss of 30-50 fps per inch of barrel.

I also find that a chronograph is a good way to keep an eye on where your pressures are at. Load for accuracy, and keep under max velocities (pressure) for safety and longevity of your gun. Just because your loads may not read impressively, doesn't mean they won't kill effectively at any sane range. Most folks effectively take game with factory ammo that has never been chronoed.

Handloading isn't about maximum speed!

Joel--just so you don't feel bad, your velocities are an EXACT DUPICATE of what my friend and I came up with experimenting with his 24" ruger. I was disappointed to see 'em below 2800 to!! I'm starting to have alot of respect for those factory hornady and federal high energy loads now!
About 5 years ago my friend bragged to me how he was getting 3100 fps out of his 7 mag with 160's. I took over my chrono and I think he was doing about 2900 fps. He said "ill show you" and went back in the house with his 3 empty shell casings, and came back out 5 min later. I don't think the first one broke 3000 and he couldn't get the bolt open. I still rass him about that to this day over a beer or two!! Never did ask him what he put in that shell.

Everything I though would be slow was fast, and vice versa the first time I ran my loads over a chrony.

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www.rifleshooter.com

I've fallen victim to this phenomenon as well, guess anyone with a reliable chrono is!
Every barrel is different, as Saeed suggests, it just seems that ALL of mine are slow. That's why I'm always very skeptical about someone's Xmm mag giving velocities 200fps higher than I've ever recorded! And that goes for factory or handloads.

I'm not sure how many reloading manuals I have, but there is a big discrepancy in loads between manuals. I use the manuals as a starting point. I have loaded powders 10% and more above some manuals max. with no pressure signs. Then again I had one Lot of powder that the starting load wouldn't even fit in the case.

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JD

I'm going to do the unpardonable and suggest that you retire the chronograph to moth balls for awhile.Your target is not nearly as impressed with velocity readings as you are.

I just want to caution folks about wantingly exceeding maximum loads in manuals. You may get away with it, you may not. There just aren't any free lunch's in internal balistics, and if you really want more speed, the answer is a bigger case and a longer tube, not stuffing more powder til the primers blow and the bolt locks up, then backing off one or two grains.

"Pressure signs" are of excessive pressure, not just a tad over max loads. They typically don't show there heads until you are past 70 kpsi, most max loads are in the 55 kpsi range. Some powders due not show linear increases in pressure or velocity as well, and on some occasions, pressures rise while velocities plateu or drop.

2700-2800 fps is entirely sufficient to get reliable performance from expanding bullets out to 300 yds and change. If you are after 400 + yard performance, then IMHO, you should consider a 3500 fps gun to really give you an advantage.

Gentlemen,

Thanks for all of the input. I must add that this "unimpressive" load of mine has accounted for eland, kudu, zebra, wildebeest, and the like, so I guess it isn't too bad...

Joel Slate
Slate & Associates, LLC
The Safari Specialists
www.slatesafaris.com

I always think that if my reloads are with in 100 feet of whats in the book I am about where they should be. I find very few rifles that shoot as fast as the books call for.

We built 4 7x57 rifles 0n Mauser actions, with barrels from the same manufacturer, used the same set of reamers and started working up loads for them with the same batches of components. When all four were at the speed we wanted, the load varied by four grains between them.

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Gerard Schultz
GS Custom Bullets

Paul hit the nail on the head when he talked about reliable bullet performance. "winning a race" is something we all dream of from being kids to grownups. So we all have "speed" in our heads. Day in and day out we all read of bullets that did not perform and almost always they are tied to velocity on the "high side" of the envelope.
When was the last time you read a post where a bullet did not perform and it was started at a speed 5-10% under max velocity?? New high tech bullets like Gerards are about to change the performance envelope but most of us are working off of technology that is 20 years old. We need to keep this all in mind!!

jrslate....ain't chronographs wonderful. the thing I really like is when the factory puts out a commercial load and publishes velocities and then at some later date reduces it but doesn't say anything...great.

DBBill,
I am not so sure if it is great....but it is interesting. I had good luck with some factory ammunition being close to the published velocity. The Speer Nitrex Grand Slam was pretty good, with most of the rounds fired averaging near 2870 fps. The Remington came in around 2820. That isn't too far off...the 230 fps off that the Nosler load was kind of bothered me...

Joel Slate
Slate & Associates, lLC
The Safari Specialists
www.slatesafaris.com

7mm Rem Mag Page www.slatesafaris.com/7mm.htm

It is well known that under controlled conditions of pressure, volume and temperature, rifles do anyway what they want to do..., on that particular day. The variables are just too many.

I use the chronograph to test the consistency of my loads and also to check that I am in the safe pressure zone(velocity is a proxy for pressure in a given rifle with a given load).

Antonio