comparing flatshooting calibres

Hales Smut

Well-Known Member
When comparing bullet drop at 300m ( as an example ) for diffrent calibres, we must start from the same point. For any calibre a max high shot at 100 m must be determined. RWS use max 4 cm high at 100m, which is about 1.6". When using this 1.6" high at 100 m as a maximum for all calibres, the drop at 300m can be very diffrent. If we can believe the catalogues a 150/160 grain 308 can drop from 3 to 5 inches more than a 130/140 grain 270 bullet. This can be the diffrence between a dead animal and a broken leg.
 
When comparing bullet drop at 300m ( as an example ) for diffrent calibres, we must start from the same point. For any calibre a max high shot at 100 m must be determined. RWS use max 4 cm high at 100m, which is about 1.6". When using this 1.6" high at 100 m as a maximum for all calibres, the drop at 300m can be very diffrent. If we can believe the catalogues a 150/160 grain 308 can drop from 3 to 5 inches more than a 130/140 grain 270 bullet. This can be the diffrence between a dead animal and a broken leg.

where did you read that?

Flatness is marketing hype unless you are shooting beyond stalking ranges.

if you exclude the 4000fps varmint calibres and the Ultra Magnums 90% of deer legal calibres when zeroed +1" at 100yds will be there or there abouts at 200yds and around 6-8" at 300 yds

Norma 130gr .270 is +1.3, 0, +6.4" for 100, 200 and 300yds http://www.norma.cc/en/Products/Hunting/270-Winchester/Soft-Point/
Hornday 150gr 308 is +1.6, 0 and 7.2" at 100, 200 and 300yds http://www.hornady.com/store/308-Win-150-gr-GMX-superformance/

I know I cant shoot well enough to put down a 1.2" difference at 300yds to the "flatness" of the calibre I am shooting. more chance its just my shooting!

almost all of these calibres have a 4" MPBR of with +/-30yds with very few exceptions
the only exceptions are breaking 3100-3200fps MV

http://www.chuckhawks.com/rifle_trajectory_table.htm

.243 Win. (95 BT at 3100)*.379+2.5"+2.3"3"@150300
.243 Win. (100 Sp at 2960).351+2.6"+1.9"3"@140283
6mm Rem. (100 Sp at 3100).351+2.5"+2.2"3"@150296
.243 WSSM (100 Sp at 3100).351+2.5"+2.2"3"@150296
.240 Apex (100 Sp at 2900).351+2.6"+1.8"3"@135278
6x62mm Freres (100 Sp at 3300).351+2.4"+2.5"3"@150312
.250 Sav. (100 Sp at 2820).336+2.7"+1.6"3"@125270
.257 Roberts (100 Sp at 3000).336+2.6"+2.0"3"@150286
.257 Roberts (120 Sp at 2780).391+2.7"+1.6"3"@125271
.257 Rob. Imp. (115 BT at 2900).453+2.6"+1.9"3"@140286
.25 WSSM (120 Sp at 2990).391+2.5"+2.0"3"@145291
.25-06 Rem. (100 Sp at 3210).336+2.5"+2.4"3"@150305
.25-06 Rem. (120 Sp at 2990).391+2.5"+2.0"3"@145291
6.5x54 (140 PSP at 2400).435+2.9"+0.2"3"@115238
6.5x55 (125 NP at 2875).449+2.6"+1.9"3"@135284
6.5x55 (140 Sp at 2645).435+2.7"+1.2"3"@125260
6.5x57 (140 SP at 2740).465+2.7"+1.6"3"@130272
.260 Rem. (120 Sp at 2890).433+2.6"+1.9"3"@135284
.260 Rem. (140 Sp at 2750).435+2.7"+1.6"3"@125271
6.5-284 Norma (140 PSP at 2900).435+2.6"+2.0"3"@140286
6.5mm Rem. Mag. (140 PSP at 2900).435+2.6"+2.0"3"@140286
6.5x65 RWS (127 Sp at 3313).449+2.4"+2.6"3"@160323
6.5x68 S (140 Sp at 2990).435+2.6"+2.1"3"@150294
.264 Win. Mag. (120 Sp at 3300).433+2.4"+2.6"3"@160321
.264 Win. Mag. (140 Sp at 3100).435+2.5"+2.3"3"@150303
6.8mm Rem. SPC (110 BTSP at 2500).360+2.9"+0.5"3"@125243
6.8mm Rem. SPC (115 Sp at 2800).325+2.6"+1.3"3"@130267
.270 Win. (130 Sp at 3140).416+2.5"+2.4"3"@150305
.270 Win. (140 AB at 2950).496+2.6"+2.1"3"@140293
.270 Win. (150 Sp at 2900).481+2.6"+2.0"3"@138287
.270 WSM (130 Sp at 3206).416+2.4"+2.4"3"@150311
.270 WSM (150 Sp at 3150).481+2.5"+2.4"3"@150311
.270 Wby. Mag. (130 Sp at 3375).416+2.3"+2.6"3"@150326
.270 Wby. Mag. (150 Sp at 3245).481+2.4"+2.6"3"@160320
7-30 Waters (120 FP at 2700).195+2.9"+0.4"3"@125238
7x57 (140 BT at 2660).485+2.7"+1.3"3"@125264
7x57 (175 Sp at 2540).519+2.8"+1.0"3"@125256
7mm-08 Rem. (120 Sp at 3000).343+2.6"+2.0"3"@140287
7mm-08 Rem. (140 BT at 2860).485+2.6"+1.9"3"@140285
7x64 (140 BT at 3000).485+2.6"+2.2"3"@150298
7x65R (175 Sp at 2650).465+2.7"+1.3"3"@125262
.284 Win. (150 Sp at 2750).456+2.7"+1.6"3"@130272
.280 Rem. (140 BT at 3000).485+2.6"+2.2"3"@150298
.280 Rem. (160 Sp at 2890).475+2.6"+1.9"3"@140287
.300 Sav. (150 BT at 2630).435+2.8"+1.2"3"@125259
.307 Win. (150 FP at 2600).268+2.8"+0.5"3"@120243
.308 Marlin (160 EVO at 2660)*.400+2.8"+1.2"3"@130261
.308 Win. (150 BT at 2800).435+2.7"+1.7"3"@135275
.308 Win. (165 Sp at 2700).410+2.7"+1.3"3"@130264
.308 Win. (180 Sp at 2610).483+2.8"+1.2"3"@125259
.30-06 (150 BT at 2910).435+2.6"+2.0"3"@145287
.30-06 (165 Sp at 2800).410+2.7"+1.7"3"@135273
.30-06 (180 Sp at 2700).483+2.7"+1.5"3"@125269
 
Just the printed Norma catalogue that I picked up at the small Belgian Game Fair this year.

Just checked RWS ammo. Both KS bullet.
270 / 130 grain / + 4cm at 100 m / - 27,4 cm at 300m
308 / 165 grain / + 4 cm at 100m / - 41,6 cm at 300m
diffrence is 14,2 cm or 5.5 inch.

That superformance is not representive I think? I plan to buy a 308 to stalk and pratice on the range. ( Cheap training ammo as I do not reload )
I agree that flatshooting is not everything, but it probably makes life easier if it's difficult judging the distance.

My point is that if you zero your rifle so that the bullet never rises above 1,5" above the line of sight the diffrence in drop of the bullet becomes more important with the slower calibres.
 
I would prefer to check the real MV of the bullet out of my rifle.
Sometimes ammo manufacturers show off a bit with figures. In one case they use data from a 29" barrel. (With hunting ammo)
Either way, it shows neither the 308 nor the mighty 270 can be point and shoot to 300m.
If one shoots at game above 200m the safest is to laser the distance and adjust scope. Second best is hold over dots or lines on
a FFP scope. Hold over points on a second focal plane would be too risky for me.
edi
 
As I don't handload I have to trust the data given in the ammo catalogues. My first rifle to buy will be a 308 for the knwon reasons. I just think when you take into account human errror when shooting, the less bullet drop the easier it is to get the bullet in the vital parts. At 300 metres all calibres will need compensation. I also think it's better to avoid shooting at 300m , but that's one of the data you find in the catalogues.
Edi, do you have any idea how those mil dots compare to the traditional n° 4 in low light? Are they thick enough to be visible with slightly older eyes?
 
Possibly better than trusting the data on the ammo box is to have a rifle 100% zeroed at 100m or yds and then see how many clicks are needed
to hit your 300m or yds target. Try get the average and make up a drop chart from that data. Might have to use the bc that the catologue
uses but the speed you reverse find out with a ballistic program.
You'll be astonished how accurate it is at say 250 or 350 after dialing in.
The reticles are different on almost all scopes. Must check individually on the scope spec. FFP/SFP and the width of the lines at x distance and mag.
Had a 4-16x50 S&B varmint reticle with, If I remember right 4mm at 100m line thickness. When set at 4 mag I couldn't see a thing at low light, at
8 or 12 mag it was half ok but not great.
edi
 
low mag usually gives better light gathering in lower light than higher mag.
That is right, but to the eye on a ffp scope the crosshair line gets finer with lower mag. That's why this is not really a low light reticle.
Think it's called varmint 8. You can imagine a line that is 0.14" thick at 100yd only magnified by 4 is hardly visible in day light.
At 16 the line is well visible but as you say light gathering.
If you like I can post you the S&B PDF that explains it better.
edi

African Jack,
plenty practice at longer ranges will sort that.
At least you'll learn when not to shoot due to wind.
Stalkers head into the wind, little effect. ha ha
Anyway I don't think Hales is talking of much more than 300m
edi
 
you never had a cross wind or a incoming quartering wind lucky you 270 130g 10mph 7inch aprox 20mph 15inch aprox
 
you never had a cross wind or a incoming quartering wind lucky you 270 130g 10mph 7inch aprox 20mph 15inch aprox

at 300yds though
most people would never attempt a 300yd shot in a 20mph wind

with a 200yd zero (1" high at 100) wind deflection data for 10mph is less than an inch out to almost 150yds.
3" at 200yds
 

There is no such thing as a flat shooting round !
Get to know your rifle/calibre set up and go from there.
 
you never had a cross wind or a incoming quartering wind lucky you 270 130g 10mph 7inch aprox 20mph 15inch aprox
The best thing is to learn to read the wind. The more you shoot the better you get at it. In some cases just dial in the windage, if not sure don't shoot.
Wind is one part, drop, trigger pull, avoiding canting and a few more factors all play a role. Hunting at extended ranges cannot be taken lightly.
I think Hales wantsto have a sniff at it and is approaching it from the right angle with plenty range and practice time. Even if he never shoots an animal at an extended range, it will be no loss and the experience will make him a better shot at normal ranges.
By the way, we have enough wind in Ireland.
edi
 
Number one priority is to make a clean kill.
Not to satisfy ones ego with either a long range shot or a stalk to with a record short range just to take
an awkward shot at a jumpy animal.
edi
 
Sorry if I put you on the wrong foot. In no way I want to promote long range shooting at game. I prefer to have a 100 m shot than having to shoot at 300 m. A clean kill is the most important. My English probably isn't good enough to be 100% clear. I'll try better.
Sometimes you see comparisons between a 270 and a 308 with only 1,5" diffrence in drop at 300 m. The 270 shoots 1,5" high at 100 m, the 308 2,3" high at 100m. I tried to explain that the only fair comparison is , giving them the same 1,5" high at 100m and than measuring the diffrence in drop at 300m.
300m = because this is one of the data easely found in catalogue . Mostly you find the data for 50/100/150/200 and 300m .
 
Personally I do not see taking a shot at 300 metres as "Stalking". Just my opinion of course, but I would suggest that the fall of a bullet at 300 metres is of interest to target shooters and snipers rather than "Stalkers".
 
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