Rifle movment when shoting slugs

[zan89]

Hi,

Today i was shooting slugs from 29 to 38gr.

I have never noticed so much jumping of a rifle when shooting pellets, yes they are lighter as slugs. But anyway i dont have ao much of a jump comaparing with king heavy in 32gr then slugs 32gr. Is there some explanation for that. Problem is that i think that soms big groups with slugs are big because rifle is much more sensitive to perfect possition behind the rifle. So i belive pellets allowes not so perfect "hug" of a rifle. When i noticed that i was holding rifle realy soft without pressure anywhere and i got one big hole with slugs at 50m. Before that shoting "normaly" like i usually do with pellets group was 2" or more.

Any toughts about that?

 

[ackuric]

Test your break force on the projectile...more break force = more push back upon the initial push, and friction also increases this effect further as projectile moves down barrel.



That is when comparing two projectiles of identical / near identical weight shot at identical velocities.

 

[8thman]

Slugs are slower exiting the barrel than pellets and require more follow through of the shot. That’s an observation I have found the first time that I started using the slugs, and reminds me of both a muzzle loader and a crossbow. I hope that helps 

 

[Motorhead]

This is correct as I understand physics ...

If said projectile starts moving earlier in the shot cycle and its acceleration is more progressive the felt recoil will be LESS than a projectile that sits there and then violently accelerates.

As Matt states it is one of barrel fit and break away friction that is the distinction you witness between a Pellet and Slug of similar weight.





JMO tho ....

 

[bandg]

This is correct as I understand physics ...

If said projectile starts moving earlier in the shot cycle and its acceleration is more progressive the felt recoil will be LESS than a projectile that sits there and then violently accelerates.

As Matt states it is one of barrel fit and break away friction that is the distinction you witness between a Pellet and Slug of similar weight.





JMO tho ....

Sounds quite logical.

 

[wimpanzee]

I experienced the same phenomenon. I had assumptions that were parallel to the provided explanation, so thank you guys for confirming!

 

[ackuric]

I experienced the same phenomenon. I had assumptions that were parallel to the provided explanation, so thank you guys for confirming!

Our pleasure!



Doing some quick napkin math, you get the following:



Pellet:

1.5 lb break force

requires roughly 30 psi of pressure build up to start pellet movement in a .25 cal and closer to 35 psi in a .22 cal

Slug 4 lb break force (ball parked, many slugs I have tried required a lot of seating forces unless sized perfectly)

requires roughly 90 psi of pressure build up to start pellet movement in a .25 cal and .100 psi in .22 call



Nearly 3x the force required to even begin movement...and then you calculate a bit of friction as it goes down the barrel, and there you have it.



You essentially feel the 'break force' and some additional bore friction. The break force can be even higher (or lower) than the 4 lbs I calculated above (all depends on slug fitment to bore)

 

[thomasair]

In 22 caliber on my rifle...I noticed no discernible difference in rifle movement when switching from pellets to slugs.


Most of the felt recoil is due to the rocket blast effect out the muzzle. This is easily proven with the addition of a good muzzle brake. A plausible explanation of why the rocket blast effect might increase with slugs is that a persons first instinct to correct a slower shooting projectile is to increase the hammer. There is a fine line between making good power with good efficiency and making a little more power with dismal efficiency.



Mike 

 

[Vetmx]

I agree. That’s why shooting slugs out of a Leshiy is a frustrating experience. It’s almost like shooting a springer. The gun is going to jump the same with every shot if you let it. The problem is letting it in different shooting situations. That’s why dead heavy or longer more comfortable guns, for me, are more consistent with slugs.

 

[Yo]

Add more weight to the gun to lessen that effect. Yo!

 

[Yo]

Someone smart should come up with a GISS type system to cancel that jump based on projectile weight. Perhaps a weak mini user adjustable gas piston as a counter? I get Royalties! Yo!

 

[Yo]

Speaking of an adjustable Gas Spring or Gas Ram in a PCP as a hammer spring alternative that would eliminate the very need for an HDD or FFHD or SSG or TIC TAC TOE or EE AI EE AI OH or whatever fancy schmancy device etc... Royalties Baby! Yo!

 

[Motorhead]

STEYR has had such a device for YEARS on there LG100 / 110 rifles.



Sorry .. no royalties for YO

 

[mr.grimm]

Hi,

Today i was shooting slugs from 29 to 38gr.

I have never noticed so much jumping of a rifle when shooting pellets, yes they are lighter as slugs. But anyway i dont have ao much of a jump comaparing with king heavy in 32gr then slugs 32gr. Is there some explanation for that. Problem is that i think that soms big groups with slugs are big because rifle is much more sensitive to perfect possition behind the rifle. So i belive pellets allowes not so perfect "hug" of a rifle. When i noticed that i was holding rifle realy soft without pressure anywhere and i got one big hole with slugs at 50m. Before that shoting "normaly" like i usually do with pellets group was 2" or more.

Any toughts about that?

I want to know ware did you get 32gr JSB King Heavies from?

 

[Bob_O]

Unless it really bothers you, recoil does not affect accuracy.

Also, I've never experienced hold sensitivity with any of my rifles.....FX or other brand.

 

[ackuric]

If you sense different recoil with the same weight and same velocity and the only change is the projectile, then the answer has already been given as to why, its not jet blast from the projectile leaving the muzzle and residual pressure on the muzzle...two identical weighed and driven projectiles will have the same muzzle jet blast...

 

[thomasair]

My apologies....I must have missed the part where the OP said he was shooting the same weights of projectiles at the same velocity.


Mike

 

[Motorhead]

My apologies....I must have missed the part where the OP said he was shooting the same weights of projectiles at the same velocity.


Mike

Mike,

I see this as similar to being in a car stopped and then accelerated to lets say 100 mph and have 10 seconds to do so.

When you start out accelerating Slowly then exponentially speed up your no where as set back in your seat as you would be with a Hard & rapid acceleration. Both make it to 100 mph, just one gets up to speed quicker.

Difference being how ABRUPT the mass is brought into motion ... a pellet being it breaks free and starts down a barrel GENERALLY easier than a bullet does would exhibit less felt recoil than a similar weight bullet that if it stayed still until higher pressure was behind it would be brought up to near equal speed quicker exhibiting more felt recoil.



I agree this being the case IF and only if the point in pressure peak behind either is different when either breaks free and starts moving. If BOTH break free and start moving at the same time & pressure behind them, then there should be no difference in recoil.



In my thinking anyways ...

 

[8thman]

When I compare pellets to slugs, the slugs are noticeably slower exiting the barrel. I am talking about the recoil. But that’s just me.

 

[oldsparky]

When I was young I lived in a small town and just about everybody went deer hunting. Almost everyday you would find me at the range. Around the end of September early October folks cam out from all over to sight in there deer rifles. A bunch of guys were down at the range talking about how their magnums would recoil. One young kid had an old savage 110 30-06 he told us he was having trouble sighting it in and was getting scared to shoot it more because of the recoil. A few guys shot it and it was something horrible. And it patterned like a shotgun. He was just about out of his factory 150 grain cartridges and was broke. I told him I had a bunch of .06 loading material and I would work with it and figure out why we couldn’t get it sighted in. When I got home I cleaned my guns, and went to clean his. I couldn’t hardly push a brass brush soaked in Hoppes down the barrel. When it did came out there was all kinds of green crud. I never saw anything plugged up like it was. It was a wonder we didn’t bulge the barrel. That rifle never did shoot great but it would go on to kill deer for him. Long story but makes me wonder if your slugs don't have more resistance than pellets, either being larger diameter or harder lead.

In no way would I think your rifle is dirty just an example from a memory that was fun to remember