Effect of number/type of grooves on velocity

Well, you missed the boat partially. The reason for shooting differently isn't because of groove/bore differences alone.
Certainly that can be a part of it, and by your pressure trace results; proves there isn't much difference between grooves and pressures.
What you have to consider is the whole systems, and not the parts. Those rifles all have the the potential to have differences in:
Chamber dimensions, free bore, bore/groove dimensions, how sharp the rifling ramps to full height, barrel length, barrel harmonics, rifling.

The most likely cause for the pressure differences, are in the chamber and freebore differences.
The most likely cause for the differences in where they shoot, is barrel harmonics.

View the original article here

311 165 grain PB-what velocity

I was given a NOE mold 311 165Gr. RF 4 cavity PB (RD) by a guy at work. He wants me to cast him some boolits. He wants to use these in the 30-30 and 30-06.Although I only cast and shoot lead for 9mm and 45, I have not done rifle boolits. It is my understanding that a GC is required at any rifle velocity to prevent leading. Can you experience rifle casters guide me?

It is my understanding that a GC is required at any rifle velocity to prevent leadingNope. A plain base boolit is fine at moderate velocities, if cast out of an appropriate alloy and fit appropriately to the gun in question.

I would say 1400 FPS as a top end velocity, but it really is going to be determined by the rifle.

Nope. A plain base boolit is fine at moderate velocities, if cast out of an appropriate alloy and fit appropriately to the gun in question.Don't forget the proper lube.

I normarlly use 45-45-10 for pistol; good for rifle >1400 FPS?

You may not post new threadsYou may not post repliesYou may not post attachmentsYou may not edit your postsForum Rules

Abbreviations used in Reloading
Pointed Soft Point "Core Lokt"

View the original article here

Ideal velocity for the 405 grain cast 45-70 boolit.

Looking for opinions on the ideal velocity range that works good for the 405 grain 45-70 boolit in a 22 inch barrel.

I prefer something in the 1400fps range. Accurate in my marlin cowboy, a bit more authority than bp velocities, yet not abusive.

I prefer something in the 1400fps range. Accurate in my marlin cowboy, a bit more authority than bp velocities, yet not abusive.I am assuming that you still get good knockdown out to 200 yards?

You may not post new threadsYou may not post repliesYou may not post attachmentsYou may not edit your postsForum Rules

Abbreviations used in Reloading
Pointed Soft Point "Core Lokt"

View the original article here

Calculating energy and velocity loss.

I am sure there are formulas for this but was wondering if there is a basic standard I can follow to calculate energy and velocities. For example my 243 cast loads at 1700 fps are approx. 560 foot pounds at the muzzle.

How do I figure my velocities and energy's at 100-200 etc..

Vmathias, go to handloads.com and use their ballistic calculator. You can get velocity, drop, and wind drift. There is input for boolit size, weight, style which will give the ballistic coefficient which in turn factors into your trajectory. The link is

http://www.handloads.com/calc/index.html

There is a lot of interesting stuff there

"Silence in the face of tyranny implies consent, and I do not consent." Mike Vanderbough, April 20, 2013

Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can name

"Ever since I arrived to a state of manhood, I have felt a sincere passion for liberty" Ethan Allen

Her is the RCBS balistic coeficients which will give you something to works off

RCBS Cast Rifle Bullet Ballistic Coefficients
22-055 FN .159
243-095 .258
257-120 .272
270-150 .327
7mm-145 Silh. .272
7mm-168 SP .306
30-115 SP .175
30-150 FN .220
308-165 Silh. .286
30-180 SP .293
30-180 FN .255
35-200 FN .243
357-180 Silh .210
375-200 FN .220
44-200 FN .130
429-240 Silh .186
45-300 FN .207
45-405 FN .303
45-500 FN .365

A 7x57 and a 404, all a man needs anywhere,anytime,ever.

Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can nameNo, I am still on the basic Pantech phone. Someday I will upgrade. lol.

Another useful ballistic tool is JBM - Calculations. You have to get the BC by relating to a similar bullet listed but you can put in your own values. Here's the link; http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

Regards
303Guy

?It is hard enough to remember my opinions, without also remembering my reasons for them!? Nietzsche

Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can nameSo what is that app?

Larry Gibson

You may not post new threadsYou may not post repliesYou may not post attachmentsYou may not edit your postsForum Rules

Abbreviations used in Reloading
Pointed Soft Point "Core Lokt"

View the original article here

New Pro Chrono velocity results

My son got a new Pro Chrono this past week and the first rounds tested were Rem, Golden bullet 22's. From a Buckmark pistol they were all over the place from 950 to 1058 fps. No surprise they don't shoot well. Next was my 45 ACP and my handloads with 200 gr. cast over 6 gr. SR 7625. These were consistent @ 950-960 fps. I checked two reloading manuals and Lyman's 45th edition shows max load of 6.2 gr for 864 fps. Speer shows 932 fps for the same load with jacketed 200 gr. HP. I have never considered this 6 gr. load as hot for our guns and was surprised by the extra velocity with .2 gr. less powder. Just wonder if the readings can be correct.
My bad, I didn't know he fired another load. These ran where they should, 885-914 fps.

Last edited by DLCTEX; Today at 02:48 PM.

Boolit Buddy Join DateFeb 2011LocationBredasdorp South AfricaPosts61

DLCTEX, living South Africa, I would not know much about your loads since we do not get SR 7625 over here, however one would expect that with your load of 6.0 gr that you should be in the 850 f/sec region? I have been shooting 200gr boolits in my 1911's for more than 30 years now, and to get them up to 1000 f/sec is pretty stiff.
Be that as it may, as far as your chronograph readings are concerned, if you place the chronograph in direct sunlight you could get readings with 100 f/sec offset to when you put it in the shade. It is best to put it in shade, constant lighting is very important for accurate/consistent readings....maybe this could be part of your problem?

Cronographs measure the light change over the sensors. Besides the bullet, it can sometimes catch the muzzle blast's pressure wave front as it passes over. The easiest way to avoid this is to move the Crono back a bit.

Boolit Buddy Join DateMar 2013Posts53

i have that same chrony, if it is facing the sun it can give screwy results...

My bad, I didn't know he shot another load. Reviewing the correct group of readings put the velocity right where it belongs, 885 -914 fps.

You may not post new threadsYou may not post repliesYou may not post attachmentsYou may not edit your postsForum Rules

Abbreviations used in Reloading
Pointed Soft Point "Core Lokt"

View the original article here