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View Full Version : S&W M69 2.75 Inch verses Ruger Redhawk 2.75 Inch



44MAG#1
09-16-2019, 08:11 AM
Here is something I've hesitated to post but will. On 8-05-19, the same day I chronoed the loads in the other post; I ran this load: 270 grain Keith type bullet, 8.2 grains Unique, CCI 300 primer, Starline cases, 1.695" OAL.

S&W M69 846.1 FPS
Ruger Redhawk 904.4 FPS

This is why some of the chrono results cause some new people to chronoing to get surprised when testing their "Pet" loads.
As I have said many times ballistics is an ever changing thing and no factory or lab or anyone has a firm grip on it.

Larry Gibson
09-16-2019, 09:40 AM
I do find, and appreciate, the data you post from your velocity testing on this thread and others. It is interesting because the variations amply demonstrate to those who don't know or don't have a grip on it the fact that there are variations, sometimes seemingly large variations, in velocity between different firearms with a given load. You should not hesitate to post such.

However, I would disagree with your opinion based on the results of this informal test. The ballisticians at factories or labs I know fully understand the velocity outside of expected test to test variation of a given load will vary not only from similar revolvers of different makes and even sometimes with revolvers of the same make. It is well known the effect on velocity variations in cylinder length, throat dimensions, barrel/cylinder gap and variation in forcing cone dimensions can have. They, along with numerous knowledgeable individuals on this forum do indeed have "a firm grip on it".

Those ballisticians and lab technicians also are quite aware of lot to lot variations in components and the attendant effect on variations in velocity let alone the test conditions when the data was collected. I don't know any of them that would state if asked what velocity you would get with your load in your revolver. None of them would tell you with your load, will get "904.4 fps" out of your Ruger Redhawk revolver with a 2.75" barrel. Most of them, myself included, will tell you what they got with a similar load out of, perhaps, a similar revolver. The fact is they do have "a firm grip on it".

The science of Ballistics is not "ever changing". What does change within expected parameters is the data obtained from simple chronograph testing such as yours. That there will be a difference as shown in your results is to be expected.......a difference yes but the exact amount......no.

Larry Gibson
09-16-2019, 12:38 PM
Not a problem, that clarifies my misconception of what you meant. You are correct. very well put in that last post. Thanks.

Texas by God
09-16-2019, 03:21 PM
Grandma summed up ballistics with "It just beez that way sometimes- sometimes it dont".

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