why do people shoot 58-65gr. bullets in .243 cal.

[j_22250]

I know that may be the smallest cal. some people own, but why not use a 22-250 or 22-250ai with better BC's and SD? The only reason I can think of is the short stubby bullet makes PD's SLAT better.

Enlighten me.

 

[Tommie]

Several of reasons, actually.

1) As you said, some people may not own a .22 centerfire and need their 6mm to do double duty.

2) Assuming similar powder charge, bullet weight, rate of twist, pressure, etc, etc the larger diameter bullet will always have a higher muzzle velocity. For comparison, look at 6mm-250 loads versus 22-250 loads on the Hodgdon site.

3) While a 55 grain .22 will have a higher SD,unimportant when shooting PD's) when compared to a 55 grain 6mm, the .22 does not necessarily have a significantly higher BC. Check out Hornady's site and look at the ballistics for .22 and .243 caliber bullets. It's an eye-opener!

4) Generally speaking, a 6mm bore will live longer than a .22 bore when similar bullets are driven at similar velocities. The larger bore has an expansion ratio advantage.

5) And as you pointed out, the light 6mm bullets have major splattage.

That's all I can think of at the moment, but surely someone will chime in with other advantages of the light 6mm bullets.

Tom

 

[30378]

In varmint hunting there is this thing called air time. The greater frontal area of the 6mm bullet in my opinion creates more air time for the varmint when hit. The 22s seem to punch through while the 6mms seem to have more impact and sling the varmint greater distances. JMHO!

 

[j_22250]

i'm not sure on your air time theory. theoretically if your rifle is on a level rest and you drop a bullet from the muzzle to the ground it takes the same time to hit the ground as it would traveling through the air; until gravity causes it to hit dirt. it may travel 3-400 yrds. two different cal. bullets the same weight should hit at the same time. a 6mm bullet would creat more drag depending on type tho; so it may be slower, but only by a few miliseconds proly.

I looked in my hornady manual an BC's are prety darn close. I'll stick with my 22-250 for the light stuff tho. 87gr. HP are perfect 4 coyotes and deer. Better energy too, jst in case you have to reach out there and touch something!!!

 

[janderson0]

i'm not sure on your air time theory. theoretically if your rifle is on a level rest and you drop a bullet from the muzzle to the ground it takes the same time to hit the ground as it would traveling through the air; until gravity causes it to hit dirt. it may travel 3-400 yrds. two different cal......QUOTE]

He is not talking bullet air time, but what the bullet causes to happen.

 

[CatShooter]

i'm not sure on your air time theory. theoretically if your rifle is on a level rest and you drop a bullet from the muzzle to the ground it takes the same time to hit the ground as it would traveling through the air; until gravity causes it to hit dirt. it may travel 3-400 yrds. two different cal......

He is not talking bullet air time, but what the bullet causes to happen.

"... but what the bullet causes to happen IS air time!


.

 

[people]

One of my friends shoots a 243 at PD and uses those 65gr bullets the same ones I use in my BR he shoots them because the 55 do not shoot as well. The other,main I think) is speed. He loves to see PD explode with his 243. They shoot way faster than the 100gr he shoots for deer.

 

[tightneck]

The simple truth is that most shooters simply like SPEED, accuracy and barrel life come second.

 

[memilanuk]

We used to describe that as 'hang time'... or another way of putting it... da bullet goes in one side... and there *is* no 'other side'!!!

Hydraulic shock waves are a beautiful thing.
:thumb:

 

[j_22250]

oooooh, you've got my curiosity working now; this is the first i've herd of air time. I still don't quite understand what yall are talking about tho. Is it air that builds in front of the bullet that when it impacts causes it to explode faster??

esplain more for me.

 

[Bushtaka]

Along the way i got confused,,,is "air time" the same as "dwell" ?

 

[7stwhunter]

I think what they mean by "air time" is when you shoot that nice prarie dog with the extra frontal area of a 6mm bullets transfers more energy and the air time is how long that dog stays flyin

 

[Tommie]

j_22250

If you haven't been prairie dog shooting, all this talk about "air time" sounds strange. It's a term used for the explosive hydrostatic shock of a varmint bullet hitting a small target which results in the target,ie: prairie dog) launching straight up into the air. I've seen many prairie dogs blast three or more feet into the air.

Watch this video. It'll answer your question about air time.

http://www.rmvh.com/Movies/Rocket.wmv

 

[Sandy]

Ah, now I understand. A varmint shooter's version of "knock-down power". Knock-up power.

 

[j_22250]

oh okay, i feel ya now. Your tring to launch those babies. Haha, I like it. kinda like shooting ground squirrels with a 17 hmr or 22 mag. Cool.:thumb: