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Re: where to start with powder charges? New to loading

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04 June 2004, 07:32
CDH
Re: where to start with powder charges? New to loading
Quote:

Blacktail, well yes & no. Vel. does have a relationship to pressures. You are not going to get high vel. w/o higher pressure, all things being equal in the same cartridge.



True. The problem is that it does not do so in a uniform and predictable manner. For example, a tight bore can 'hold' the bullet and increase pressures while reducing velocities. Ditto a short throat. Yes, 'all else being equal' higher pressure means more velocity, but some seem to believe that reading the velocity gives you insight into actual (not relative) pressure. This is just not always true.

Therefore, using a chrono to tell velocity and equating that to safe pressures vs. load manuals is not always accurate, and assuming it is so can get one into trouble.

This is why I don't bother with a chrono. Just my 2c worth!
04 June 2004, 07:49
Reloader
Dogcatcher,

If using a good Bolt Action or Single Shot rifle, you will probably get your best groups when loading at or slightly above the maximum loads listed in a particular manual.

Most of the Load Data producers lower there loads for liability reasons. You will see that the published maximums vary from book to book. I would incourage you to start out a couple of grains below the published max and then work up but, be on the look out for pressure signs.

I have always gotten the best accuracy w/ a full case or even a compressed load in some cases. I would not advise to use compressed loads for a "newbie."

Have fun w/ this new addictive hobby and Good Luck!

Reloader
04 June 2004, 12:38
Atkinson
A chronograph has a lot to do with pressure IMO, it is a great reloading aid...It can show you pressure spikes, it can be a wake up call for too hot a load, it can do a lot of things when used in combination with other red flags....

I have shot some hot loads that gave absolutly no indication of being a bit too much with new brass, and the chronograph said "Whoa, something ain't right, thats too fast for this caliber etc."...To say that all it does is register velocity is only a half truth, velocity tells us a bunch...

It is imparative when reloading for a double rifle...
04 June 2004, 12:47
Hot Core
Quote:

... the chrono can be helpful in seeing trends & deviations. If my vel. isn't going up in a linear fashion as I increase powder, but pressure looks ok, it may be time to stop where I am.



Hey Fred, I do agree with you about the above. That doesn't concern me at all. What concerns me is someone like "dog" trying to understand what it means as a Beginning Reloader.

It is very easy for people to forget that a Beginner does not have the "knowledge base" necessary to understand that Velocity can do exactly as you said - reduce the "Rate of Increase"(Velocity) while the Pressure continues to increase.

...

Quote:

... I also like to know what my actual vel. is not guess, & that's what you do by looking @ published data.



Hey Fred, Got a couple of questions for you. I'm not in any way trying to put you on the spot. If you believe that is my intention, ignore these questions.

Q1. Once you know what the "actual vel. is" for a Load, what do you do with that info?

Q2. Let's say you looked at three Load Manuals and a particular Load showed 2750fps, 2850fps and 2950fps for 5x.xgr of H4350 and a 165gr Bullet. Lets then say you took your chronograph and found your Velocity was somewhere between 2750-2950fps. What difference does it make?

Q3. Just to be totally clear for "dog", do you agree that Velocity DOES NOT equal Pressure?
04 June 2004, 12:49
Hot Core
Hey CDH, Excellent post. You obviously "understand"!