Velocity loss in a semi vs manual action

[JD848]

Originally Posted by gtr

Some people still believe that a person needs a 7mm stw for deer.

if you like the stw ,by all means shoot what you want,elk11 is an stw guy,i sure don't think he is stuck with one cartridge ,but if he likes it and he has lotsa hours of experience with that gun and knows it inside out,why wouldn't he,i shoot what I like ,another shoots what he likes,plus I have couple semi's with the same cartridge in a bolt and have cross checked them for speed and there very close in my crony,nothing to worry myself over and the test's were done with reloads and factory ,the only difference for me is heavy snow in trees and cold temp's and the semi's stay home and my bolt actions are used.

[700-223]

Originally Posted by JD848

if you like the stw ,by all means shoot what you want,elk11 is an stw guy,i sure don't think he is stuck with one cartridge ,but if he likes it and he has lotsa hours of experience with that gun and knows it inside out,why wouldn't he,i shoot what I like ,another shoots what he likes,plus I have couple semi's with the same cartridge in a bolt and have cross checked them for speed and there very close in my crony,nothing to worry myself over and the test's were done with reloads and factory ,the only difference for me is heavy snow in trees and cold temp's and the semi's stay home and my bolt actions are used.

Would you mind sharing any more details? Specific rifles, cartridges or results?

[Nyksta]

Originally Posted by 700-223

Would you mind sharing any more details? Specific rifles, cartridges or results?

Maybe people dont feel like advertising on the internet what guns they own for everyone to account for

[elkhunter11]

Originally Posted by JD848

if you like the stw ,by all means shoot what you want,elk11 is an stw guy,i sure don't think he is stuck with one cartridge ,but if he likes it and he has lotsa hours of experience with that gun and knows it inside out,why wouldn't he,i shoot what I like ,another shoots what he likes,plus I have couple semi's with the same cartridge in a bolt and have cross checked them for speed and there very close in my crony,nothing to worry myself over and the test's were done with reloads and factory ,the only difference for me is heavy snow in trees and cold temp's and the semi's stay home and my bolt actions are used.

His post had nothing to do with a specific cartridge, it was just another feeble attempt at a personal attack towards myself. He takes cheap shots at myself and a few other people at every opportunity, just like he did on another forum, until he was banned there.

[58thecat]

Looked up some data on the Internet and marginal differences in velocity loss so not enough to hinder performance.

[Grizzly Adams]

Let's put this differently. How much more gas is just wasted following the bullet out of the muzzle, than tapped off by a tiny hole ? A significant amount.

Grizz

[gtr]

Originally Posted by elkhunter11

His post had nothing to do with a specific cartridge, it was just another feeble attempt at a personal attack towards myself. He takes cheap shots at myself and a few other people at every opportunity, just like he did on another forum, until he was banned there.

You have an aversion to the truth. I replied to your comment that pheasant hunters think they need three inch twelve gauge shells . In reality if you hunt released tame birds, over a dog that is overkill. If you hunt wild birds, not released birds, sometimes a center fire would be nice. Depends how you hunt. Tame or wild animals, fenced or released makes a difference on what tools you use.

[Dean2]

Originally Posted by Grizzly Adams

Let's put this differently. How much more gas is just wasted following the bullet out of the muzzle, than tapped off by a tiny hole ? A significant amount.

Grizz

Seems like there was WAY more GAS wasted in this thread than has ever been wasted in a SA.

[catnthehat]

Originally Posted by gtr

You have an aversion to the truth. I replied to your comment that pheasant hunters think they need three inch twelve gauge shells . In reality if you hunt released tame birds, over a dog that is overkill. If you hunt wild birds, not released birds, sometimes a center fire would be nice. Depends how you hunt. Tame or wild animals, fenced or released makes a difference on what tools you use.

The guys I hunt with hunt wild birds quite often with 20's and 28's with no issues, but we hunt where we don't need to take 50 yard shots.
This whole derail has nothing to do with semi autos and velocity however.
The velocity difference in real life is insignificant except for Sunday morning internet musings.
Cat

[JD848]

TO elk11 I was not taking a cheap shot,infact in was the told opposite I was giving you 100 percent respect on your abilities for shooting your stw and that a guy shoots what he likes,your reading this wrong ,infact I thought the cheap shot was about guys that needed to still hunt with an 7mm stw in an upper post and I said I thought you had lots of experience with it and handled it well,giving all the good things,i have no idear about what your doing here,i honestly was on your side and if you don't believe that then you need to reread that post,never meant to disrespect you in any and gave you all the respect I could on that post.i am not even going into that other parts because you are wrong ELK11,I honestly thought it was an attack on you,i am writing this as good as I can very upset you would turn on me for know reason online like that,IT WAS ALL RESPECT DAMIT.Why would a guy not hunt with what he doesn't likes and since you used the 7mm stw and your proud of it I used you as example of a guy that loves that cartridge ,we have not agreed on all things but I never ever cut you down,infact always agree on most stuff about the stw,i owned one and we went a few times over it an the 7mm re mag,but never cut you down,your wrong mister and don't even thing you are right.

[elkhunter11]

Originally Posted by JD848

TO elk11 I was not taking a cheap shot,infact in was the told opposite I was giving you 100 percent respect on your abilities for shooting your stw and that a guy shoots what he likes,your reading this wrong ,infact I thought the cheap shot was about guys that needed to still hunt with an 7mm stw in an upper post and I said I thought you had lots of experience with it and handled it well,giving all the good things,i have no idear about what your doing here,i honestly was on your side and if you don't believe that then you need to reread that post,never meant to disrespect you in any and gave you all the respect I could on that post.i am not even going into that other parts because you are wrong ELK11,I honestly thought it was an attack on you,i am writing this as good as I can very upset you would turn on me for know reason online like that,IT WAS ALL RESPECT DAMIT.Why would a guy not hunt with what he doesn't likes and since you used the 7mm stw and your proud of it I used you as example of a guy that loves that cartridge ,we have not agreed on all things but I never ever cut you down,infact always agree on most stuff about the stw,i owned one and we went a few times over it an the 7mm re mag,but never cut you down,your wrong mister and don't even thing you are right.

I wasn't referring to you at all in the remark about a personal attack, I was responding to you to explain why the other poster posted what he did.

[covey ridge]

Originally Posted by trooper

It seems to me that with a gas operated firearm, the gas port is further down the barrel. wouldn't the projectile have reached max velocity by the time the projectile passes the gas port where some of the energy is bled off to recock the action? Maybe a blowback action would be different?
I'm thinking that if the breech is locked when the round is fired and doesn't unlock and start it's rearward motion until the bullet passes the gasport, the bullet should have reached the same MV that a bolt gun of the same caliber would.

^^^^^^^^^^ If I thought it made a difference, I would buy this explanation.

[JD848]

Just read it wrong I guess,i thought cause my post was above your comments ,that you were referring to me,all is good life goes on,CHEERS

[covey ridge]

Originally Posted by JD848

TO elk11 I was not taking a cheap shot,infact in was the told opposite I was giving you 100 percent respect on your abilities for shooting your stw and that a guy shoots what he likes,your reading this wrong ,infact I thought the cheap shot was about guys that needed to still hunt with an 7mm stw in an upper post and I said I thought you had lots of experience with it and handled it well,giving all the good things,i have no idear about what your doing here,i honestly was on your side and if you don't believe that then you need to reread that post,never meant to disrespect you in any and gave you all the respect I could on that post.i am not even going into that other parts because you are wrong ELK11,I honestly thought it was an attack on you,i am writing this as good as I can very upset you would turn on me for know reason online like that,IT WAS ALL RESPECT DAMIT.Why would a guy not hunt with what he doesn't likes and since you used the 7mm stw and your proud of it I used you as example of a guy that loves that cartridge ,we have not agreed on all things but I never ever cut you down,infact always agree on most stuff about the stw,i owned one and we went a few times over it an the 7mm re mag,but never cut you down,your wrong mister and don't even thing you are right.

Well. when I read this thread, I thought the jab came from gtr and not you!

I thought elk was as responding to your post but referring to the jab from gtr.

I think when it comes to guns and hunting discussions most people would get along well face to face without key boards and screens.

Politics and ethics, not so much

[gitrdun]

[58thecat]

Originally Posted by gitrdun

It's so warm outside I thought we would be a happy bunch.....

[700-223]

Originally Posted by Nyksta

Maybe people dont feel like advertising on the internet what guns they own for everyone to account for

Maybe.

I'm sure if that's the case he'll let me know. No harm in asking, right?

[700-223]

Originally Posted by Dean2

Seems like there was WAY more GAS wasted in this thread than has ever been wasted in a SA.

Comment of the day!

[Coiloil37]

Well this thread self destructed like expected.

Conditions at the range weren't very good, a mix of light and heavy snow/ sleet but I got what I said I would.

I didn't chrony every shot because I didn't want that much water/snow/rain on my chronograph and it wasn't wearing it's rain jacket. So I took one velocity for every setting which is next to useless but there wasn't THAT much variation, probably not much more then what I would see if I shot six rounds over the chrony on the same gas setting.
The blocked setting did give a slightly higher velocity and I did shoot two at that setting just to confirm and got 3080 and 3087 fps

The first pic is of the six, three shot groups (one on each gas setting). All with the same load. The shot marked fowler was the first one down the pipe on a clean barrel. I probably should of shot two because the next shot wasn't with its group. In hind-site I probably should of shot the first two or three over the target but this is what we've got. I started top left, worked to the right on the top row, then again bottom row left to right. The numbers are the gas setting used.



This is a six shot group, one on each gas setting and when I got the velocity readings.



The two flyers don't make a lot of sense to me. I didn't keep track of which shots landed where but looking at the other six groups I would of expected more of the shots to have imprinted down in the blue diamond instead of as high as they did. Maybe it was me, maybe the snow or maybe the gas setting.

And for the confusion about velocity with a semi or shorter barrel. This load is about 150 fps slower then the book would suggest with a 24" tube.

[Sashi]

The velocity of a bullet is dragged down considerably, from either a SA or bolt action, as it passes through a Chrony. Learnt that this morning.

[Okotokian]

Sounds like, as is the case in so many other discussions we have here as to which is better, yadda yadda yadda, there's less real world difference than one might think?

[colroggal]

Originally Posted by Coiloil37

Well this thread self destructed like expected.

Conditions at the range weren't very good, a mix of light and heavy snow/ sleet but I got what I said I would.

I didn't chrony every shot because I didn't want that much water/snow/rain on my chronograph and it wasn't wearing it's rain jacket. So I took one velocity for every setting which is next to useless but there wasn't THAT much variation, probably not much more then what I would see if I shot six rounds over the chrony on the same gas setting.
The blocked setting did give a slightly higher velocity and I did shoot two at that setting just to confirm and got 3080 and 3087 fps

The first pic is of the six, three shot groups (one on each gas setting). All with the same load. The shot marked fowler was the first one down the pipe on a clean barrel. I probably should of shot two because the next shot wasn't with its group. In hind-site I probably should of shot the first two or three over the target but this is what we've got. I started top left, worked to the right on the top row, then again bottom row left to right. The numbers are the gas setting used.



This is a six shot group, one on each gas setting and when I got the velocity readings.



The two flyers don't make a lot of sense to me. I didn't keep track of which shots landed where but looking at the other six groups I would of expected more of the shots to have imprinted down in the blue diamond instead of as high as they did. Maybe it was me, maybe the snow or maybe the gas setting.

And for the confusion about velocity with a semi or shorter barrel. This load is about 150 fps slower then the book would suggest with a 24" tube.

Interesting results. Like you said, not entirely definitive, but the velocity changes are linear.

I'd say from blocked to wide open your losing the equivalent of something less than 2 inches of barrel length. It's interesting that your second pic shows a horizontal spread as the gas setting changes. Just shows wind and/or changing barrel harmonics play a bigger role in poi than a few dozen feet per second.

Thanks for posting.

Colin

[Chargerguy]

I don't see a linear drop. Setting 1 and 4 are nearly identical.

[Jack fish hunter]

Originally Posted by colroggal

I'd like to see that. A box of match grade say .308 . Ten out of a bar and 10 out of an Xbolt - same twist and barrel length. The results would be interesting.

Anyone got about $2500 to offer up in the name of science?

Colin

It's Alberta. So no. Lol

[colroggal]

Originally Posted by Chargerguy

I don't see a linear drop. Setting 1 and 4 are nearly identical.

From blocked to 5 and at points in betweent velocity decreases. I assume there is some variables at play with the velocity of individual rounds. As Coiloil37 stated and I concurred with, the test is not definitive, but for the rounds he chronographed velocity decreased with each increase in the gas setting - if we account for chrony errors and standard deviation.

Colin

[Chargerguy]

Originally Posted by colroggal

From blocked to 5 and at points in betweent velocity decreases. I assume there is some variables at play with the velocity of individual rounds. As Coiloil37 stated and I concurred with, the test is not definitive, but for the rounds he chronographed velocity decreased with each increase in the gas setting - if we account for chrony errors and standard deviation.

Colin

Yes, each gas setting resulted in a velocity lower than the blocked setting. But there's no linear decrease. I'm sure if more rounds were fired and average taken we'd see it. If I can get my XCR out one of these days I may give it a try with the Labradar.

[Speckle55]

you guys got it all wrong

if I fire the first shot then fire others one after the other

i get the drafting effect

my 29 bullet is how much more effective

just saying I love my semi

roflmao

Food for Thought

David

[bb356]

Originally Posted by Speckle55

you guys got it all wrong

if I fire the first shot then fire others one after the other

i get the drafting effect

my 29 bullet is how much more effective

just saying I love my semi

roflmao

Food for Thought

David

[densa44]

I don't care all that much about MV. But I am very interested in finding the "sweet spot" where the vibration of the muzzle has stopped. I think in your experiment it is somewhere between target 2 and target 4. You have a couple of holes touching.

I'll leave it to those much more qualified than me to expand on this information. Aiming for the "one hole target" vary the amount of powder, weight of bullet or adjust those "gas knobs" I just read about. I only own one semi auto and it is an sks so know nothing about knobs for gas settings.

Again thanks for doing the experiment, I always enjoy reading posts where members have tried to shine a light on the conversation.