Accuracy versus velocity

[ButterBean]

I'm just starting to develop an accuracy load for a new 300WSM. Less than 75 rounds down the barrel and new brass. Best accuracy is at/above max (stiff bolt lift and prominent ejector marks). Backing down to acceptable pressure reduces velocity by about 70 fps and opens groups to around .6 moa (vs .4 moa at top end). Shooting a mono for deer/elk, so velocity and accuracy important. Maybe another 50 shots and fire formed brass will get me more speed and better accuracy?

What bullet are you shooting, I just put together a 300WSM that is freaky fast and accurate

 

[ButterBean]

I tend to agree. Started out with a 25-06 and was told to use biggest bullet possible. Turned out at 2800 fps it usually poked a hole. One hit at 209 yds and the deer acted like wasnt even hit. Then went to smaller bullets and found the 87 grn to be the ticket. At 3550 fps yes the deer could tell the difference. Longest shot with that fast little bullet was 440 yds facing head on. Dropped. Eventually experimented with bigger cartridges. The longer yardages need better accuracy. 1.5" straight taper barrel with big single shot action, Jewell trigger, 12-42 NF scope and 30-378 and 338-378 with no freebore and You can have cake and eat it too. Have different twist barrels for both and can shoot small to large bullets. Velocity is addicting and yes you can also have accuracy.

I've been on the same road with the heavies, all will do the job but the static shock is fascinating to me, We used 220 swifts for Crop Damage on Deer for years with a 70 HP, They would run 50yrds and fall over, No Blood No holes but the innards were jelly, I'm anxiously awaiting Deer Season so i can see what the WSM is gonna do

 

[FlyGuy11]

What bullet are you shooting, I just put together a 300WSM that is freaky fast and accurate

My hunting guide is a huge fan of the 300 WSM and he uses 168 grain Nosler Ballistic Tip Hunting (Part #30168).

 

[Philward]

I prefer the flattest trajectory I can get, but I rarely shoot beyond 300 yds so I use a lighter bullet than the heaviest for caliber. Consequently that flat trajectory comes a little easier. 200g bullet in 30-06 for elk in timber, 120-130 g bullet in 7-08 for deer, 100-110g in 257 cal for deer, 150-160 in 7mmRM, 130-140g with 270 win.

 

[Pointman]

Since my hunting days are in the "rearview mirror", my concern is accuracy over velocity. That being said, wj=hen considering long-range, out to and including 1000 meters, velocity is a concern. When the projectile goes subsonic, it's subject to wind more but more often the round gets "wonky". The spin is what makes them accurate, which is why the Kentucky rifles were vastly superior to the old Brown Bess muskets. I have found that using a chronograph helps a bunch. Interestingly, my two long-range rifles have accuracy nodes at low and approaching maximum. That be the case, I will opt for the higher velocity every time. My opinion only.

 

[Mc Fraser]

Anyone got this going? What seating depth, velocities? Killed anything with it? I shot the precision hunter factory loads into a .2, 6 shot group yesterday. However the ES was 48 FPS and my average velocity was only 2905. Would like to get that es down below 20 and velocity up to 3000.
let me know what you know. Thanks

When working up loads for hunting does it really matter to get that extra 150-200fps if your personal limits are 400yds and under , seem like I find pretty good load on the lower end of powder charges often or right around max , but I'm not a long range shooter don't really see any benefit to pushing it to the limit. Is there another take on this? Or other reason I'm not aware of pushing faster

In my experience, there is no advantage of an extra 150-200 fps when shooting under the condition outlined above. Less speed means less recoil, better accuracy, some bullets perform better at lower speeds, they expand better and hold more weight.

 

[Wolf76]

Accuracy over velocity, with any size cartridge, shooting any bullet, at any range.

Without accuracy, the rest doesnt matter.

Kind of a garbage statement. There are a number of circumstances where the velocity is critical to bullet performance (minimum fps for expansion), especially at longer distances.
Example: 308 -168gr NBT bullet 2500 vs 2800 fps - 1800 fps minimum for expansion
Let's say the 2500 fps load shoots .5 MOA and the 2800 fps load shoots 2 MOA.

The 2500 load falls below the minimum at just over 400 yards
The 2800 load falls below the minimum at just over 550 yards.
AND the 2800 load will still hit within 6" from point of aim @550. Plenty enough to kill deer and elk.
Even though I skewed the example in favor of the slower more accurate load, you see a real world example where velocity was more important. Now, most guns shoot 1.5 MOA or better and several guarantee sub moa.
The only time your example applies is when one load shoots acceptable accuracy and the other does not, and/or target shooting.

 

[Critter Picker]

Accuracy first.
Good rangefinder second , knowing what the load will do at various ranges. I can always add a click or 2 in ,but can't overcome inaccuracy.

 

[Buck Fever]

I notice no one has commented on the fact allowable wind reading error is driven far more by accuracy than by velocity. For example, let's say I am trying to hit a 10 inch target at 800 yards. I have two cartridges shooting identical bullets (suppose a 7mm 195 Berger), but one shoots .4 MOA @ 2800 and the other one shoots .8 @ 3000. The 2800 fps bullet is going to group 3.2" at 800 yards, which if perfectly centered, leaves 3.4" on either side of the widest bullet impact. At 800 yards the slower bullet is drifting 3.2" per mile of wind speed. So your allowable error to keep that entire group size in the 10" vital area is 1.1 mph. The faster bullet drifts 2.8" per mile of wind speed, but since the group is 6.4" if perfectly centered, you only have 1.8" on either end, which means you must estimate wind speed to within .64 mph. The slower but more accurate load has TWICE the allowable wind reading error. I will take that every time.

Bullets don't travel in a straight line; half hit to the left, and half hit to the right. Half are higher than your point of aim and half are below.

Some of you are probably thinking you can hit that 10" target quite frequently and yet cannot estimate the wind within 1 mph. Remember, if the wind is left to right and you call it too high by 1 mph (pushing your "group" 3.2" left), there is a 50% chance the bullet will be one that hits to the right of your point of aim, potentially resulting in what looks like a perfect wind call.

One thing is rather obvious: at some point your ability to call the wind and/or shoot a small enough group at extended ranges will result in wounded animals. You can work up loads and spin on custom barrels till the cows come home, but unless you are out there shooting at LR at least weekly, you are going to suck at reading the wind. And if you are shooting in a mirage-less condition, you are really going to suck.

I said very long shots. If you recalculate at 1,200 yards I think the results will look different.

Not that I think I could shoot accurately enough at 1,200 yards for hunting but at some point the lines cross and the lines are going to be different for every situation.

I also said it's a corner case and it is a small corner but there it is.

 

[Tree Farmer]

ButterBean, I'm shooting a 166 Hammer Hunter using StaBALL 6.5. I tried several other powders, but this one gave me the best velocity, accuracy and
ES. Pressure signs showed up at around 3200 while a comfortable load is at 3120 +/-. I want accuracy and terminal energy to 500 yds (will practice farther). I think I can get a little more velocity as the barrel breaks in. Please share any info or thoughts.

 

[RYEWSKY25284]

I would not worry about velocity as long as the energy threshold goal is met. I am an Elk hunter and I prefer to harvest my animals at a maximum range of 500 yards and I regularly practice out to this range and further. The energy minimum at 500 yards for me must meet or exceed 1500 ft. lbs. of energy. This has not been an issue since I have moved to the 28 Nosler.

nice Bull. It's interesting to watch the bullet trail up to impact

 

[LRNut]

I said very long shots. If you recalculate at 1,200 yards I think the results will look different.

Not that I think I could shoot accurately enough at 1,200 yards for hunting but at some point the lines cross and the lines are going to be different for every situation.

I also said it's a corner case and it is a small corner but there it is.

Actually, it is even worse at 1200 than 800 (funny, those are the two ranges I practice at least weekly). The .8 MOA load will group 9.6 inches, leaving .2 inches of allowable wind error. At 3000 fps, that Berger drifts 7.1 inches for every mile of wind. You would have to guess the wind perfectly; within three hundreds of a mile per hour.

The same bullet at 2800 but shooting .4 MOA would group 4.8 inches, leaving you 2.6 inches on either end. The bullet drifts slightly more (7.9 inches per one mile of wind) but your allowable error is .3 mph, 10 times that of the faster bullet.

Incidentally, probably not a popular thing to point out here, but TOF is 1.7 seconds, so assuming you can call the wind to within .3 mph, you need it not to vary by that much during the TOF (not going to happen) or you may not hit. So much for wounding...

Again, these numbers are for a 100 percent probability of a hit. You can be pretty sloppy with your wind call and still hit 50% of the time.

One final (maybe) observation: any shot in which you get feedback (a small gong, watching the bullet impact, looking in a spotting scope, etc) will cause you to naturally adjust and if you shoot enough in one sitting, you can delude yourself into thinking you are great at wind calls. For example, I used to take one shot at 800, then look where I hit, then shoot at 1200 (different angle, so the wind was different). Knowing where I hit at 800 was hugely beneficial. Yesterday I called the wind 2 MOA at 800 (Edge, 2820 w/ Berger 300s) - it was blowing pretty hard from behind to about 7 o'clock - a wind I hate, since the angle changes so fast and has a much larger impact than the same angle change but from 3 or 9 o'clock. I didn't see the impact, but swung around to shoot at 1200. Mirage was different, so I called the wind 5 mph vs the 6-7 (full value) call I had at 800. My SIG said 2.25 MOA. But I always check mirage using the side parallax on my NF scopes, and thought it had picked up, so I held 3 MOA L. Elevation was a few inches high but windage was 1.25 MOA left - a huge miss. But, at 800 I had a perfect wind call. If I had looked at the 800 yard shot, I would have held closer to 2 than 3 (because the 1200 yard rock is a 3/4 wind vs a 9 oclock wind at 800).

 

[Buck Fever]

I think you are evaluating this a bit wrong trying to fit it within 10". Just compare the wind drift and similar wind read errors. Fairly large wind read errors too, like I said, if you suck at reading wind.

 

[mwkelso]

Kind of a garbage statement. There are a number of circumstances where the velocity is critical to bullet performance (minimum fps for expansion), especially at longer distances.
Example: 308 -168gr NBT bullet 2500 vs 2800 fps - 1800 fps minimum for expansion
Let's say the 2500 fps load shoots .5 MOA and the 2800 fps load shoots 2 MOA.

The 2500 load falls below the minimum at just over 400 yards
The 2800 load falls below the minimum at just over 550 yards.
AND the 2800 load will still hit within 6" from point of aim @550. Plenty enough to kill deer and elk.
Even though I skewed the example in favor of the slower more accurate load, you see a real world example where velocity was more important. Now, most guns shoot 1.5 MOA or better and several guarantee sub moa.
The only time your example applies is when one load shoots acceptable accuracy and the other does not, and/or target shooting.

2 MOA at 550 yards is just over 11", not 6".
If someone is only gaining 300fps and willingly losing 1.5moa of accuracy, I would be very concerned.
The person who is willing to shoot an animal with that mentality will likely be tracking many wounded animals. Or putting animals through unnecessary pain until death. Or worse, both.