Why is it so hard to shoot subs?

[dellet]

Just a discussion to get people thinking. There is a lot of frustration shooting subs with any kind of precision. There are some very good reasons for it, I'll throw a couple out there.

The basic premise is that subs at 100 takes about the same skill as some other cartridges at 3-500.

Because the math is easy I chose a Ruger 204 as an example.
50 grain bullet @ 3000 fps.
25 grains powder
8 Pound rifle 24" barrel
Recoil 3 pounds energy, 4.91 fps velocity, Impulse 1.22 lbs second

300 Blackout
220 grain buillet
11 grains powder
8 pound rifle 8" barrel
Recoil 3 pounds energy, 4.91 fps velocity, Impulse 1.22 lbs second.

Lock time and bullet exit.
The time from trigger pull to primer strike, to bullet exit is almost exactly the same. Recoils is exactly the same. But what about time of flight to target?

300 Blackout 100 yards = .3 seconds
204 Ruger 300 yards = .3 seconds, 100 yards = .1 seconds.

Not wanting to get into bullet weight and wind resistance, just looking at the amount of time given for things to go wrong or change that you have to compensate for.

Then you have the time from trigger pull until bullet exit. In the example that we know is not really completely correct and we could get the exact numbers in Miliseconds, but the basic point is trigger control.

Given the examples, If barrel length was the same at 24", you would have to multiply the amount of time available to screw up the shot with poor shooting skills by three for the sub load. It would be the same with an 8" and somewhere in the middle with a 16".

It's not easy shooting subs at 100, What are other issues that need to be dealt with and how to they compare to shooting supers at longer ranges?

[Bob the nailer]

I’m no marksman/competitor by the standards of other talented shooters on the forum, I do spend large amounts of time at the bench shooting and reloading. With subs at longer ranges (100 yards +) I think induvial shooter discipline and repeatability to execute the shot is paramount with accurate point of aim shot placement. With that said subsonic cartridge prep with benchrest type procedures will produce very accurate loads, if time is spend finding that sweet spot with charge/primer/bullet/seating depth ect..
Time of flight with subs plays havoc on the bullet as it lobs out to its mark with hopes that the yaw places it on center of point of aim. Oh yes it’s fun to tune an accurate load to sub-moa and watch the paper tare open on impact, damn dellet now see what you did I want to leave work early and burn some powder!

[rebel]

I had two customers in here that shoot 300 subs.( Both Contenders, one integral suppressed, one screw on.) I read them dellets post and asked for their input. Both repeated some of what you both have said. One stated that ( integral suppressed ) if he rested the forearm it would shoot high. He claimed it was something to do with the short heavy barrel and I chose not to argue. ( Two piece stock , my Handi will shoot off every time like that )
My opinion will fall in the hunting realm of things since you boys pretty much covered paper punching. Watch the hole you are shooting through when hunting. At around 50-60 yards that bullet is higher than you think.

[dellet]

I’m no marksman/competitor by the standards of other talented shooters on the forum, I do spend large amounts of time at the bench shooting and reloading. With subs at longer ranges (100 yards +) I think induvial shooter discipline and repeatability to execute the shot is paramount with accurate point of aim shot placement. With that said subsonic cartridge prep with benchrest type procedures will produce very accurate loads, if time is spend finding that sweet spot with charge/primer/bullet/seating depth ect..
Time of flight with subs plays havoc on the bullet as it lobs out to its mark with hopes that the yaw places it on center of point of aim. Oh yes it’s fun to tune an accurate load to sub-moa and watch the paper tare open on impact, damn dellet now see what you did I want to leave work early and burn some powder!

You're in luck, just looked at the calender it's National

[TreeTopFlier]

Just a discussion to get people thinking. There is a lot of frustration shooting subs with any kind of precision. There are some very good reasons for it, I'll throw a couple out there.

The basic premise is that subs at 100 takes about the same skill as some other cartridges at 3-500.

Because the math is easy I chose a Ruger 204 as an example.
50 grain bullet @ 3000 fps.
25 grains powder
8 Pound rifle 24" barrel
Recoil 3 pounds energy, 4.91 fps velocity, Impulse 1.22 lbs second

300 Blackout
220 grain buillet
11 grains powder
8 pound rifle 8" barrel
Recoil 3 pounds energy, 4.91 fps velocity, Impulse 1.22 lbs second.

Lock time and bullet exit.
The time from trigger pull to primer strike, to bullet exit is almost exactly the same. Recoils is exactly the same. But what about time of flight to target?

300 Blackout 100 yards = .3 seconds
204 Ruger 300 yards = .3 seconds, 100 yards = .1 seconds.

Not wanting to get into bullet weight and wind resistance, just looking at the amount of time given for things to go wrong or change that you have to compensate for.

Then you have the time from trigger pull until bullet exit. In the example that we know is not really completely correct and we could get the exact numbers in Miliseconds, but the basic point is trigger control.

Given the examples, If barrel length was the same at 24", you would have to multiply the amount of time available to screw up the shot with poor shooting skills by three for the sub load. It would be the same with an 8" and somewhere in the middle with a 16".

It's not easy shooting subs at 100, What are other issues that need to be dealt with and how to they compare to shooting supers at longer ranges?

I guess the only thing I could come up with to add to the difficulty in accuracy would be the types of bullets often used. Many of the heavy sub bullets are cast and coated. I would guess that they would have less consistency in terms of radial balance and concentricity so they may not spin as true. Compared to a jacketed struck or swaged into a uniform die?

I have shot some jacketed 225 and my perception was they were very accurate at 50. Didnt take them to 100.

[dellet]

Cast bullets probably contribute, but it’s not the bullets fault. It takes a lot more understanding of certain things to shoot cast well.

This is a target shot by an acquaintance on another forum. 154 grain .28 cal bullet. He did cheat as far as this discussion goes, in that velocity was probably around 1500 fps. It does show what someone capable can do with cast bullets. That 10 shot group is probably no bigger than 1 1/4”.



He doesn’t shoot that way every day, but my understanding is that day he backed this 250 up with a second score of 249. If I remember right the 25 ring is 1 1/2”. That gives you an idea of his twenty shot group size.

[TreeTopFlier]

Just a thought. I wonder about the physics of sonic vs subsonic.

Is the supersonic flight environment (envelop) more favorable to accurate flight than sub sonic? We know that bullets can get destabilized transitioning to subsonic.

Air reacts very differently on surfaces of a supersonic item than a sub sonic.

[dellet]

Just a thought. I wonder about the physics of sonic vs subsonic.

Is the supersonic flight environment (envelop) more favorable to accurately than sub sonic? We know that bullets can get destabilized transitioning to subsonic.

Air reacts very differently on surfaces of a supersonic item than a sub sonic.

That’s actually a huge part of it, or should be if you’re serious about groups.

There are long range bullets specifically designed to shoot through the transonic speeds. Basically 950-1350 fps. Any bullet for Palma class takes this into account. They are some of the most stable designs out there.

Another example is Precision air rifles. A projectile that weighs 20 grains bounces pretty easy. Most of those folks tune their guns to keep velocity under the low end of transonic.

The difference in the bullets arc over 100 yards between 1000 and 950 fps is relatively small.

Using a 220 SMK as an example, with a 100 yard zero, 1000 fps bullet will have 1/2” less arc (4.5” vs 5”)than the 950 fps. And both will drop about an inch in the last 5 yards.

[Ballistic Edge]

Gents
I would like to chime in. In my experience I don't find it difficult to shoot the subs. But in all honesty I don't shoot them much past 150-200 yds max.
I think the reason is, I have shot a ton of handguns all in the velocity range that subs move in. Over the years and by today's standards I would have been considered a pro. There was no such thing in my day. After I quit and stepped away the first big money contract was signed by Rob Latham for a Million.
I also think that moving from Handguns to rifles is a lot easier than moving from a rifle to a handgun. Before you dismiss me think about it, the subs are about the same weight and velocity as a 45acp. only thing they have going for them is they are a little more aerodynamic. So if you are used to handguns then it makes the subs easy as you are already used to trajectory and follow through required. I think about the 300 as a glorified 45acp.
So I am at home with the slower velocities that these subs move at. I like to visualize it as a 45acp going down range. In fact to further confirm a prior comment , try shooting a 45 acp target type load at 100 yards and watch the bullet go down range it does not fly like you think. It is a lot higher. It reminds me of a baseball and impact sounds just like a hard thrown fast ball. They all curve in also just like a baseball.
Sorry to ramble but I look at it different.
This may give a little different perspective.
Phil

[dellet]

Gents
I would like to chime in. In my experience I don't find it difficult to shoot the subs. But in all honesty I don't shoot them much past 150-200 yds max.
I think the reason is, I have shot a ton of handguns all in the velocity range that subs move in. Over the years and by today's standards I would have been considered a pro. There was no such thing in my day. After I quit and stepped away the first big money contract was signed by Rob Latham for a Million.
I also think that moving from Handguns to rifles is a lot easier than moving from a rifle to a handgun. Before you dismiss me think about it, the subs are about the same weight and velocity as a 45acp. only thing they have going for them is they are a little more aerodynamic. So if you are used to handguns then it makes the subs easy as you are already used to trajectory and follow through required. I think about the 300 as a glorified 45acp.
So I am at home with the slower velocities that these subs move at. I like to visualize it as a 45acp going down range. In fact to further confirm a prior comment , try shooting a 45 acp target type load at 100 yards and watch the bullet go down range it does not fly like you think. It is a lot higher. It reminds me of a baseball and impact sounds just like a hard thrown fast ball. They all curve in also just like a baseball.
Sorry to ramble but I look at it different.
This may give a little different perspective.
Phil

I think you’re absolutely right.
It’s that different way of thinking that people have trouble with. MOA with a decent rifle comes pretty easy. But the skill set to do that with a pistol takes a bit more thought and quality control.

Fun day example.
At the local range last summer I was set up on the 200 yard range and some friends came out of the pistol bay. They had 22 pistols. Anybody that has asked for scope advice for subs has probably had Dolomite chime in suggesting a quality 22 scope. The drops are remarkably close. Since I was shooting subs I challenged them to try the 8” gong. Using my scope as a guide I picked a spot about 48” above the gong as their point of aim. With me as a spotter one guy was on steel in 2-3 shots, another took about 10, probably a dozen at least for me.

Then the worst thing imaginable happened. One of the guys handed his pistol to his girlfriend. On steel first shot. She promptly declared the shooting session was over. None of us have lived that one down.