22/250 observed ballistics.

[Claret_Dabbler]

I have been playing with a friends 22/250 over the past week doing a bit of load development etc. I have observed some surprising results regarding bullet drop.

I have been using 50gr V-Max's and 55gr NBT's with both Benchmark and Varget. Velocity has been measured by a Chrono 10 feet in front of the muzzle. Various loads displayed velocities between 3500 and 3700 FPS, with quite big extreme spreads ( around 100FPS ). Using the classic 1" high at 100yards, I would have expected to be bang on at 200 yards given the velocity. In reality, using a 1" high zero, POA at 200 yards was a full 2" low. I had to adjust POA at 100 yards to a full 2" high to get a 200 yard Zero.

I hear a lot of chat about flat shooting 22 CF's etc, and holding dead on out to near 300 yards. These actual observed results would tend to call a lot of these claims into question.

Any comments lads??

 

[finnbear270]

Brian, if your chrony is telling the truth, maybe you are pushing the V max a bit hard?, I had some really rubbish results with them, I substituted Amax with excellent results, I have also heard people discuss V max coming apart some way down range, extreme spreads of variation could be down to primers, I'm sure Muir will have an idea on this one, Steve.

 

[Claret_Dabbler]

Steve, I just find it interesting. I bought this Chrono a few months ago, this past week was the first time we have had the weather to really spend some time working on stuff. There was certainlly no evidence of the V-maxs coming nor instability.

I have not shot my 222 or 270 over the chrono - never will now as they are both gone, but both gave results in line with rough expectations, ie 1" high zero with both gave 200 yard POI's around 2" low, both in theory were running at 3000 - 3100 FPS, the 270 maybe a bit less, the 222 maybe a bit more.

I just find it surprising that with measured velocity of say 3600FPS, that the 22/250 is not substantially flatter.

I have a new 22/250 on the way myself, should get it next week if the cops ever send out my variation which was due three weeks ago. It will be interesting to compare two different rifles shooting similar loads.

 

[finnbear270]

Maybe you have bullets it just doesn't like?

 

[Muir]

Interesting. Not so much that you would find that much drop at 200 yards with the 22-250 but more so that you would think that a three-inch window of trajectory at 200 yards isn't flat. Seems darned flat to me, what with that gravity thing to overcome and all. Still, I guess that is a little out of the expected frame of 2". It's hard to say what was going on. So much hangs on external conditions such as temp, humidity, barometric pressure and velocity. All these things effect trajectory. That Nosler bullet has a factory listed ballistic coefficient of .267 but if you could get me two chronograph readings, say 50M apart, I could calculate the actual BC at your locale. This might change the picture, ballistically, because Nosler uses computer models to generate their BC's.

I ran that bullet (Nosler) over my computer with their BC and it comes up that you are within 7/8" of the plotted trajectory. Considering all the variables, I don't know if it's worth losing too much sleep over. JMHO, of course~Muir

 

[Thar]

Another point is that the height that your scope is mounted above the bore will affect the perceived bullet drop. I would take with a pinch of salt anybody that says that there rifle will shoot to the point of aim out to 300 yrds.

I have a couple of flat shooting deer rifles and with a 200 yard zero you can aim dead on up to 250 on deer sized game with heart lung shots but above that you have to start allowing for gravity.

ATB

Tahr

 

[Ronin]

There is alot or "rubbish" spouted on forums regarding "lazer like" trajectories.

The 22-250 is no exception, its flat, to a point then succumbs just like any other calibre to the effect of gravity, drag and falling MV.

 

[Offroad Gary]

http://www.thestalkingdirectory.co....2-250-.243-and-.308-calibre-review-range-test

this is what we found out.

i now have a R93 22-250 of my own and its giving 3600 with 41gn h380, gives about 3550 with 35.5gn of h4895.

my .243 @ 3900 is flatter and harder hitting with the 55's, but the 22-250 has something about it - using it as a vermin gun for the summer with a nxs 5.5 - 22 x 56 np2 -dd.

i think the 22-250 would benefit from a longer barrel than the r93 has, but then it wouldnt be an r93, so it would not be a benefit! although the r93 varmint looks like a good bit of kit

 

[john.d.m]

Def agree with Redmists comments ref "laser like"trajectories
IMO the 22.250 is a great calibre,but, I think alot of us tend to think its better/greater/more acurate/flatter shooting than it realy is, as there is NO rifle /bullet combination that doesn`t succumb to gravity somewhere/sometime
I had mine built by C.Ferguson, and all I wanted to do was shoot foxes,and the action came back with a 26inch Schillin barrel on it and it shot the 40gr hp Federal ammo brilliantly.
Mate of mine used a Sako or Tikka forget which,with 24in barrel and it wouldnt group in 4inches with my ammo, and my rifle would only do 2inch groups with his ammo.
Over here I just use 55 gr factory stuff and it works well enough on rabbits and goats not used it on any deer yet.

 

[finnbear270]

Occasionally a rifle will, in any calibre turn in some pretty fantastic results, some calibres fairly well regarded in accuracy comps will have the odd one that outshines the rest,It may just be down to that being the case with 22-250, it's fairly well known this is a pretty good fox / deer round.......... just a bit overhyped

 

[Ronin]

I mean no offence by this;

BUT


ballistics may seem complicated (and it is if you don;t understand it), but all calibers / (bullets) are predictable in their flight path (drop)

Once you know the muzzle velocity, zero distance (exact), barometric pressure at time data otained, altitude of zero range, ballistic co-efficient of bullet and weight of bullet, you can then pretty accurately predict your drop (flight path) of the bullet.

There are no "majik bullets" or "fantasticly flat" calibres.

All (most) calibres are flatish to 200 yds (with some exceptions - 30-30 etc)

What people dont understand (or want to understand) is that drop is plottable, predictable and repeatable.

Granted if one factors into the equation wind, incline and topography sometimes you get a bottle mixed and your drop is not what is was thought it would be.

This is where the skill comes in.

Wind defelection is another matter entirely - yes predictable again, but very hard to get right first time.


I try and learn my flight path (drop) of every calibre I shoot and have tables or hand held data nearby if I require it.


Forget relying on "lazer bullets"

Although the 220 Swift would be up there as flattest, but barrel life ,,,,800 rounds.........



Apologies

Rant over, normal service resumed.

 

[Claret_Dabbler]

I suppose it is just one of those inexplicable things in rifle shooting.

Muir, Temp was around 60 deg F, humidity around 60% (guess, but roughly right), barometric pressure around 1015mB. Velocity for the 55gr NBT averaged 3575 with quite a spread. Rifle is a Howa 1500 with a 24" barrel and an ASE S5 Mod. Shots were at a downhill angle of about 10 deg.

The same rifle with 40gr NBT at just over 4000fps is spot on at 200 yards with a 1" high 100 yard zero. The answer is to shot 40's I know, but the guy wannts a heavier bullet.

Cheers.

 

[Claret_Dabbler]

Redmist, it is the very fact that ballistics are so predictable that led me to start this post.

All of the tragectory charts for a 22/250 and 50/55 grain bullets show a 1-1.25" high POI at 100 yards should give a 200 yard zero. This particular rifle seems to be well outside of this envelope. I would not have queried it if I did not have a chrono to measure the velocity.

 

[finnbear270]

What happens to that plot (projected) when you try something the rifle just does not get on with?

 

[Claret_Dabbler]

What happens to that plot (projected) when you try something the rifle just does not get on with?

Steve, the short answer is "I don't know". One particular load - 35.5gr Varget with the 55 NBT, was sub 0.5" at 100 yards, in almost a perfect clover leaf. If it was a load the rifle didn't like, I would expect just a large poor group at 200 yards. This load at 200 yards was somewhat strung out horizontal - about 2", there was a cross wind, but fell within a narrow stripe 1/2" deep consistently 2" low.

 

[finnbear270]

I had a brill group, five shots into a tanner (old sixpence for you pre decimal types ), later on , same day, Horizontal stringing set in, The loads had shot the action screws loose!

 

[Muir]

What happens to that plot (projected) when you try something the rifle just does not get on with?

Nothing. The bullets may not be accurate but they should follow a predictable (somewhat) path nonetheless...mechanicals and all being correct and secure. There are a couple of gremlins out there. One of them is that ballistic coefficient is not static. It changes during flight and it changes with initial velocity. The 33 grain V-Max bullet used in the Remington 22WMR Premier load has a BC of .136 at 2150 fps. When I shoot these same bullets from my 22 Hornet (they are available at times to reloaders as production over-runs) at 3200 fps the same equipment and mathematics gives a BC of only .089. This is just the evidence of the bullets inability to overcome the air resistance at the higher velocity. Few bullets retain their BC value with changes in velocity in either direction.

I suspect that the shooting conditions and velocity spreads affected the bullet. The velocity spreads fool with the angle of departure the bullet takes from the muzzle... Who knows what a cross wind is doing to the down range velocity bleed. For now, you can drop a round into a three-inch strip which is a tiny spot at 200M. You can retest in better weather, perhaps. ~Muir