.17 HMR rifle questions

[BULLSEYE BILL]

>Here are some pics of my surgical tool...

>Northing fancy, but it shoots well enough for me...

I bet it does.

>it looks like the scope touches the barrel, but it doesn't. I can get one dollar bill between the scope and the barrel, but 2 one dollar bills will not fit.

You need to try that when the barrel is hot, you may be surprised...

[David Stewart]

Ben,
I bought my daughter a .243 in the H&R youth model. A couple of observations I can offer regarding those single shots;
1. The barrel is considerably thicker than my Rem mod 700. This increased the weight even though the overall gun is considerably shorter and easier to handle.
2. The short barrel resulted in a surprisingly loud crack and the shot....
3. Thicker barrel resulted in it holding it's accuracy for longer before requireing a cool down- downside, it takes longer to cool off once hot. Not a factor in coyote/deer hunting but could be a considerable negative shooting p dogs.
4. Recoil was negligible however as the others said, the recoil on almost any center fire is going to be higher than a rimfire. Noteable- my daughter weighs 85lbs and had NO problem shooting targets (up to about four-six rounds and then I noticed some flinching....time to stop and hit it another day). When the moment came shooting a nice buck in an awkward position slightly twisting she of course reacted that she never felt the recoil..... Note: Has ANYONE ever felt the recoil while shooting at a deer??? Certainly not me.
5. My next gun WILL be a H&R in the 22-250 for shooting critters at long range around the house......I've made a couple of 300yd shots on coyotes with my 30-06 in the pasture but I cannot wait to try a similar shot with the 22-250 on a crow.

P.S. There is some enjoyment shooting a .22 LR at distances of 100+ yds and trying to calculate the circular bullet flight path reacting to the twist of the barrel. Not the most accurate way to put a critter down but at the price of ammo, shure is fun.

David

[BULLSEYE BILL]

>a .22 LR at distances of 100+ yds and trying to calculate the circular bullet flight path reacting to the twist of the barrel.

An interesting observation we have noticed on our 100 yard indoor range with the flight path.

Since it is economically infeasible to light the entire range, we have lights set at the 25, 50, 75, and 100 yard distances. These are the distances that the carrier stops and where the monitors are positioned.

When shooting 22lr standard velocity ammunition, you can actually see the bullets path as it crosses the lights at each distance. The bullet actually makes a corkscrew of about four to five inches in diameter! Interestingly enough bullets do not make a straight arch in it's path to the target, but makes a 'barrel roll' of sorts.

[Michael Bush]

>Has ANYONE ever felt the recoil while shooting at a deer???

No.

[Barry Digman]

"Note: Has ANYONE ever felt the recoil while shooting at a deer???"


Depends. If you hit your target, ya never feel a thing.

If ya miss a 75-yard slam dunk it feels like Barry Bonds teed off on yer shoulder.

[thesurveyor]

"Note: Has ANYONE ever felt the recoil while shooting at a deer???"


Depends. If you hit your target, ya never feel a thing.

If ya miss a 75-yard slam dunk it feels like Barry Bonds teed off on yer shoulder.

That is called pride, and it is closer to your heart is where the pain is.

Just my two cents...

[Kieck]

When shooting 22lr standard velocity ammunition, you can actually see the bullets path as it crosses the lights at each distance. The bullet actually makes a corkscrew of about four to five inches in diameter! Interestingly enough bullets do not make a straight arch in it's path to the target, but makes a 'barrel roll' of sorts. -Bullseye Bill

So, despite this apparently huge deviation during the flight of any given bullet, you still think "bolt actions are more accurate than semi-autos?" How in the world -- if a bullet is "barrel-rolling" this widely -- could you ever even tell what effect the bolt is having? The deviation in flight would be so great, from what you describe, that a difference in distance of a few feet would mean the difference between hitting the target or being off the paper, almost.

Here's a reality that is virtually the same concept.

I used to keep times for a 10K run here. There are thousands of racers. Let's look at predictions from two points of view. The first is what is the gender of the first place runner going to be? I can virtually guarantee it will be a male. The first three will be male. PROBABLY the first 10. I will be right 99.9999% of the time basing this prediction on gender.

But lets try another prediction. Let's say I pick two of the runners at random and try to predict which will come in before the other based ONLY on gender. If I pick the male, I'll be right about 50.1% of the time. If I pick the female, I'll be right about 49.9% of the time. Why? Because there are other factors. So how useful is the assumption that a given male will beat a given female? Not very.

So, if I want to be the winner of a benchrest contest, it would behoove me to shoot a bolt action because it is more likely to be in the top .0001% than a semi-auto. On the other hand if I'm picking a gun off the rack and assume that it will be accurate simply because it is a bolt action, I'll only be right about 52% of the time. If I assume it's accurate because it's a semi-auto, I'll be right 48% of the time.

I'm honestly not trying to argue with you and am probably saying what you intend to say, however the point is if you want top of the line, tack driving accuracy, you're much more likely to be able to get that out of a bolt action. If you want an accurate off the shelf gun, the odds are only a little better with the bolt action. -Michael Bush

Now, that example I can agree with. However, what you're really saying then is, "The most accurate rifle in any event is likely to use a bolt action." That's different than, "Bolt actions are more accurate than semi-autos," for exactly the reasons you describe with your example.

[Kieck]

On the "EF-5" thread, John F posted this:

I read that discussion but came late and didn't want to bring it back. I can explain why bolt action precision inherently exceeds most semi-auto and auto designs.

Short and fat has no effect on precision (what you really were asking about) but may on accuracy (the word you used) for reasons that aren't obvious (unless you do a comparative shooting).

I will only answer if you resurrect that thread. -John F

So, here it is. I'm resurrecting this thread.

And, John F is correct. What we're really discussing here is "precision," not "accuracy."

So, John F, how is it that bolt actions are inherently more precise than autoloaders?

And then, shooters have made claims that "short, fat" (SF) cartridges provide more precision in rifles than "long, skinny" cartridges for at least a couple reasons: 1) more combustion of the powder in a SF cartridge occurs in the casing and in the barrel than bombustion of the powder in a longer, thinner cartridge occurs in the casing and barrel; and this combustion is more uniform from shot-to-shot, and 2) shorter actions have less "play" and "resonance" in them than longer actions.

In my opinion, as I've stated before, any "inherent precision/accuracy" due to the action is so easily lost in or concealed by imprecision/inaccuracy of so many other factors as to be moot or negligible, at best. Some goes for the cartridge geometry, as far as I'm concerned.

So, let's hear the explanations, John F!

P.S. Have you gotten your rifle yet, Ben Brewcat? What did you end up getting, if you've gotten it, and how do you like it?

[John F]

So, John F, how is it that bolt actions are inherently more precise than autoloaders?

First, we have to set some boundaries. There are classes of guns that autoload [panzer howitzer] (or act as if autoloaded - ie. metalstorm [http://www.fugly.com/videos/5188/mil...r-minute.html]) (cool huh?) that we will not include. Specifically we will call the follow designs (common in small arms - rifles, handguns) autoloaders:

blowback operated
recoil operated
gas operated
And hybrids of the above.

We also make everything else equal, that is friction forces for bullets, powder charge mass, etc. The only thing to change are the parts related to the action.

Why is a bolt action inherently more precise? Because it does not have a dynamic volumetric chamber. The vessel size behind the bullet as the bullet moves through positions in a bolt action gun is consistent from shot to shot. In the autoloader designs, and easiest to see in a blowback design, the vessel behind the bullet as the bullet moves through any given position is not consistent from shot to shot. This difference is due the machinery necessary for the autoloading function and is affected by spring rate changes due to temperature changes, work hardening, stress, friction changes due all of the above, crud buildup in gas tubes etc. In fact, in blowback designs there is a timing issue in which the chamber can open prior to the bullets exit and the internal ballistics (pressure curve) can be quite erratic. (bad for precision)

A bolt action is one of the strongest of a class of guns that use a statically constant chamber size. Falling block and rolling block actions also show some favor in long range shooting sports (particularly handgun). Lever action rifles also exhibit this behavour.

Some autoloaders do take advantage of a statically constant chamber, such as some gatling gun designs.

And then, shooters have made claims that "short, fat" (SF) cartridges provide more precision in rifles than "long, skinny" cartridges for at least a couple reasons: 1) more combustion of the powder in a SF cartridge occurs in the casing and in the barrel than bombustion of the powder in a longer, thinner cartridge occurs in the casing and barrel; and this combustion is more uniform from shot-to-shot

This is really a function of the powder.

It is true that more of the combustion occurs in the chamber of a SF cartridge as the flame front can more easily penetrate the powder charge, the shoulders hold the charge in the case, and the burn is more from front to back. This affects felt recoil some as the initial mass sent down the barrel does not include the powder charge.

This is how accuracy can be affected.

SF cartridges are more effecient. I believe this is due a larger area of ignition and the front to back nature of combustion causing better internal ballistics as seen in strain gauge pressure maps.

, and 2) shorter actions have less "play" and "resonance" in them than longer actions.

the resonance I think you might be referring to would be barrel whip which is a function of the barrel. There can be differences in bolt action designs such as number of lugs on the bolt and whether the bolt locks into a chamber built into the receiver or the barrel etc but for bolt action guns we can say this is a pretty silly notion. Now if we are comparing lever action guns in which the lock at at the back of the bolt and the length of the bolt is in front of the lock the the length may come into play. Basically, we need to consider where the lock is in the design.

Actually, I should just say that this is a function of the design of the gun and not the length of the cartridge.

In my opinion, as I've stated before, any "inherent precision/accuracy" due to the action is so easily lost in or concealed by imprecision/inaccuracy of so many other factors as to be moot or negligible, at best. Some goes for the cartridge geometry, as far as I'm concerned.

This is all a matter of how you measure precision and the degree of precision necessary for your application. If we stick to hunting or even police sniping Then in general I would agree with you. If we are talking benchrest or long range competition or military sniping then I disagree.

The SF cartridge gives you a more effecient case geometry with less felt recoil.

[Ben Brewcat]

Hey gang,

No movement on the pea shooter yet; I've been held prisoner in the dark tower of "job" for many weeks now. Nonetheless I've taken moments to continue researching and I now think I've settled on a different tack, the Remington 700 SPS varmint in .223: http://www.remington.com/products/fi...mint_specs.asp

The difference in cartridge cost is a fair bit, but still not prohibitively expensive, and the extra range would be fun. There's lots of good varminting out here to be had. My .30-06 is a Rem 700 and I like it. The technical discussion, though WAY beyond my level, is interesting and educational (even if I never shoot at that level). Anyone have a take on the heavy-barrel, varmint-style rifles to share?

[Michael Bush]

>Anyone have a take on the heavy-barrel, varmint-style rifles to share?

I love them. My Ruger M77V .25-06 will shoot an 1/8" group at 200 yards. I adjusted the trigger a bit and bedded the action but that's as much as has been modified.

[Ben Brewcat]

Finally, got it! Picked up a used Savage 93 .17 HMR, stainless heavy barrel with a nice laminated stock. The trigger creeps a mile but it groups nicely and FUN to shoot. It's great to plink with while the .30-06 barrel is cooling.