Where are my rounds going?

[fenderstrat]

Hey guys, I'm still pretty new to shooting and I'm trying to figure out what happened. Ok, so I took my new rifle to the range yesterday, Its a K98 Mauser, refurbished by the James River Company in america, rebarreled for .308 W. So I started slow, first at 25m, and everything seemed fine, good groups, about 3 in high, so i moved on to 50 and still pretty good, about 6 in high this time. Then I moved to 100m and.... nothing. I fired 2 groups of 5 shots with nothing to show for it, the targets were intact. After that I tried shooting a little bit below the target, as well as a bit above, and still nothing.

So where are my rounds going? The logic would indicate that my shots would be 12 in high at 100m, would that be the case? I'm no expert, but I always thought that the farther away you would shoot, the more bullet drop you get. So yeah, I'm confused right now.... help?

[KWhorenet]

try a bigger target

[Chronos]

if you were 6" high at 50m then you went to 100m your trajectory would have been over 12" high and probably off target

give it about 11.75 moa clicks down and that will be roughly a 100m zero but i'd come down about 10 moa for a zero that puts you nearly 2" high at 100 and give you a MPBR of about 262m

(calcs done using a 150gr factory load at 2820fps)

Chronos

[bigfellascott]

I'd go back to the 50m and get it spot on there (ie hitting POA) , then go out to 100m and adjust it from there, sounds like she's going over (no indication from dust I take it?). also are you using a scope or not? (don't know anything about the rifle so not sure if she's a scoped job or open sights).

[bigfellascott]

What I do when I want to zero a rifle and get it on paper for the first time is set it up on a rest or bags, take the bolt out and look down the barrel and make sure I can see the target (I usually do this at 25m) I then have a look through the scope and see if I can see the target through that, I then take the shot and assuming I've got it right and got a hit anywhere on the target I then keep the X-hairs on the POA (point of aim) and just the X-hairs to the bullet hole, now the X-hairs are now aligned to the bore and its pretty much just a matter of adjusting the Vertical - I then shoot it at 100m and do any final adjustments and that's it, she's ready to go hunting with.

have a look at this video - it shows what I mean, you'll see he takes a shot which lands to the right and low, he then winds the turrets to the point of impact, then tests to see that its where it should be shooting after the adjustments.

https://www.youtube.com/watch?v=qwD5zu7yTeI

[fenderstrat]

No scope, just iron sights

[bigfellascott]

No scope, just iron sights

Roger that adjust em so they are shooting lower then, sounds like they are going over the top.

[fenderstrat]

No scope, just iron sights

Roger that adjust em so they are shooting lower then, sounds like they are going over the top.

Sounds like a plan! Except I dont know how to do that exactly. Replace the front post with a taller one?

[Chronos]

FYI my K98 in .308 (Israeli) shoots about 4" high at 100m, on service rifle targets the best hold is usually a 6 o'clock hold, this gives you a good view of the target (probably tommy)

you might need to spend a bit of time at the range before you work out your sight settings, I shot out to 375 meters a few weeks ago and after a few shots at each distance i knocked down 5 silhouette rams at that range shooting prone. interestingly the factory K98 ramp was dead on 375m for a center hit at 375m,

i think it's a matter of working out where your .308 load hits compared to the old 8mm mauser loads the sights were designed for. Do you know if JRC changed the sight ramp during rebarreling?

Chronos

[bigfellascott]

No scope, just iron sights

Roger that adjust em so they are shooting lower then, sounds like they are going over the top.

Sounds like a plan! Except I dont know how to do that exactly. Replace the front post with a taller one?

Sorry mate can't help ya with that one, been a bloody long time since I had anything to do with open sights and I don't know that particular rifle to help with it, hopefully someone will come along and provide some info on how to adjust them.

Maybe a few pics of the sights might help work it out.

[Warrigul]

No scope, just iron sights

Find a load and stick to it, having run across a similar rifle in the past the sight ramp was calibrated for 7.92 x 57 still so the only way you are going to get it right is the old way - suck it and see. Get the windage dead right first, it is described in the manual below(it is for a 8 x 57 but the principles are applicable to yours). You may need to get a taller front sight, (from memory a K98 is .003" of sight height per inch at 100) but make sure the sight leaf isn't hanging up at all first.

Good luck, let us know how you go.

http://pdf.textfiles.com/manuals/FIREAR ... user98.pdf

Also make sure the top of the front sight is level with the top of the vee, not down at the bottom.

[bigfellascott]

From what I've been reading they sound like a RPITA to adjust, do a google search there seems to be some info about how to go about it. Sounds like they are set up to shoot around the 200m range (designed that way) I think you can get different front sights to suit closer ranges - again just do some searching and see what you can find.

Good luck

[Warrigul]

Sounding like a cracked record but make sure the sights are set correctly and you have the correct sight picture.

[jays]

What I do when I want to zero a rifle and get it on paper for the first time is set it up on a rest or bags, take the bolt out and look down the barrel and make sure I can see the target (I usually do this at 25m)

I do 25m too. Get on the bulleyes at 25m which is piss easy, and I know I'll be about 3" high at 100m. Set up a tall target just in case, but never had an issue. Confirm the 100m POI and a few clicks down and your away.

With a scope of course, not iron sights as in this case.

[SendIt]

What ammo are you using Fender?

If you can tell me the bullet weight and velocity (factory ammo? says it on the pack? - or hand load charge weight?) I could put it into a ballistics calculator based on your 3" high at 25m and tell you with reasonable accuracy where they're going at 100m.

[newsteadvic]

Although the Mauser ladder sights say 100metres for their lowest setting, many people find this actually represents a 300metre zero with 8mm surplus. Then add in that you have a rifle in a new calibre with its original sights calibrated for the original calibre. The original Mauser 1935 SS patrone was 195grains and your 7.62x51is ?150grains to 180grains? Apparently the Israeli converted rifles had a new front sight to reflect the change from 8mm to 7.62x51:
http://www.cruffler.com/review-January-01.html

Its a K98 Mauser, refurbished by the James River Company in america, rebarreled for .308 W.

Did James River Mauser change the front sight? Did they do the re-barrel or did they re-furbish a Israeli rifle? It is likely you will need a taller front sight:
http://www.brownells.com/rifle-parts/si ... od341.aspx

I'm no expert, but I always thought that the farther away you would shoot, the more bullet drop you get. So yeah, I'm confused right now.... help?

Hopefully not teaching you to suck eggs but a standard trajectory looks like:


You are getting a high 25metre zero and so your 100metre impact poing is going to be even higher. As others have said you are likely shooting over the target at 100metres. Depending on the sort of range you are at, do you have the opportunity to use something large like a flat moving box or piece of gyrock behind the target? I also find round targets difficult with the Mauser sights for shooting groups and use a large inverted triangle of some thing high contrast like red card cut out and stuck on white paper.

This is the same load shot by myself at an inverted triangle and a round target. However maybe it is just my eyes that prefer this contrast and inverted triangle.

Option C is closest to the Mauser sight picture, depending on your front sight it may be more triangular and pointed or more post like if non-original.

Other approaches to increase contrast is blacking the front sight with a candle flame or painting it with red nail polish or white-out, depending on your preferences.

[fenderstrat]

The rifle is german made, 1941 production, converted to .308.

What ammo are you using Fender?

If you can tell me the bullet weight and velocity (factory ammo? says it on the pack? - or hand load charge weight?) I could put it into a ballistics calculator based on your 3" high at 25m and tell you with reasonable accuracy where they're going at 100m.

I used PPU 150 SP stuff, nothing fancy. Doesnt say anything about velocity on the pack...

edit: found some info here: http://www.ppu-usa.com/winchester-rifle-ammunition.html
apparently its 2820 fps?

Thanks a lot everyone, I guess I'll just go back to the range and do some more shooting. Pretty happy with the way it shoots, at 50ms anyways

[SendIt]

That'll work. Velocity will be a little different base on your barrel but close enough for this. For your future reference you're looking at these trajectories based on your zero distance.

100m zero
25m - 0.6" low
50m - 0"


200m zero
25m - 0"
50m - 1.3" high
100m - 2.5" high


300m zero
25m - 1" high
50m - 3.1" high
100m - 6." high
200m - 7.3" high


400m zero
25m - 2.1" high
50m - 5.4" high
100m - 10.8" high
200m - 16.5" high
300m - 13.7" high


Which brings us to..... It would seem with this ammo your sights are on about 450m, based on the following.

450m zero
25m - 2.8" high
50m - 6.7" high
100m - 13.5" high
200m - 21.8" high
300m - 21.7" high
400m - 10.7" high
450m - zero


You should be expecting a POI around 13.5" high of bulleyes at 100m based on what we've got here.

[Chronos]

The rifle is german made, 1941 production, converted to .308.

What ammo are you using Fender?

If you can tell me the bullet weight and velocity (factory ammo? says it on the pack? - or hand load charge weight?) I could put it into a ballistics calculator based on your 3" high at 25m and tell you with reasonable accuracy where they're going at 100m.

I used PPU 150 SP stuff, nothing fancy. Doesnt say anything about velocity on the pack...

edit: found some info here: http://www.ppu-usa.com/winchester-rifle-ammunition.html
apparently its 2820 fps?

Thanks a lot everyone, I guess I'll just go back to the range and do some more shooting. Pretty happy with the way it shoots, at 50ms anyways

Are you sure its .308 and not 7.62X51?

I assume if it's been rebarreled in the states its .308 but my Israeli for example is 7.62x51 and I wont use factory .308 ammo in it.

Chronos

[fenderstrat]

The shop where i bought it advertised it as a .308. The rifle is marked as 7.62 NATO. I emailed the James river company and they told me i could use either with no problem.

So... how do i fix this? Taller front blade?

[newsteadvic]

So... how do i fix this? Taller front blade?

yes, if you intend to keep using that load or one close to it.

To move the line of sight UP (the shot hit ABOVE the point of aim) the REAR sight is LOWERED or the FRONT sight is RAISED.

http://en.wikiversity.org/wiki/How_to_a ... iron_sight

The other (more expensive) option is to use an adjustable rear sight (like a Williams 5D) or a optical sighting option like telescopic options. Did James River drill and tap the rifle?

[fenderstrat]

I dont reload yet (but im definitely planning to) so I guess I'll just get a new front sight blade. too bad, the windage on this thing is spot on.

[Chronos]

I dont reload yet (but im definitely planning to) so I guess I'll just get a new front sight blade. too bad, the windage on this thing is spot on.

what are you planning to do with this gun mate?

reason i ask is if you plan on shooting it in some form of service rifle or CSD match your best bet would be to set up to reload and down load your ammo to match the sights, choose a bullet weight as heavy as you can with the twist you have

for example this may be the bullet your sight was designed for

"German cartridge variants during World War II[edit]

Karabiner 98k stripper clip with brass-cased 7.92x57mm ammunition
composite photograph of cartridge cut in half stood next to intact cartridge and base of cartridge
German 7.92 mm s.S. 12.8 g (198 gr) Full Metal Jacket Boat-Tail round.

Steel cased German s.S. ball ammunition produced in 1941.

Spitzgeschoß mit Kern, yellow bullet, red circular cap groove
The German standard s.S. (schweres Spitzgeschoß—"heavy pointed bullet") ball bullet was 35.3 mm (1.39 in) long, boat-tailed, and very well made.[19] It was lead filled, had a gilding-metal-plated jacket, and weighed 12.8 grams (197.53 gr). The s.S. ball boat tail projectile was designed for long range use and offered the best aerodynamic efficiency and external ballistic performance of any standard rifle bullet used during World War II, with a G1 ballistic coefficient between 0.593 and 0.557. When fired at the typical muzzle velocity of 760 m/s (2,493 ft/s) out of a 600 mm (23.6 in) barrel the s.S. bullet retained supersonic velocity up to and past 1,000 m"

Wiki


Chronos

[Warrigul]

I dont reload yet (but im definitely planning to) so I guess I'll just get a new front sight blade. too bad, the windage on this thing is spot on.

Try and find out where it is shooting, do it at 100m. Measure the one you have got and according to my range book .003" = 1" at 100 and this worked for me. Get one taller than you need and you can file it down.

Alternatively you can built a short one up if needed and file back.

[greyghost]

Karabiner 98k stripper clip with brass-cased 7.92x57mm ammunition
composite photograph of cartridge cut in half stood next to intact cartridge and base of cartridge
German 7.92 mm s.S. 12.8 g (198 gr) Full Metal Jacket Boat-Tail round.

200gr... They weren't screwing around.

[Warrigul]

Karabiner 98k stripper clip with brass-cased 7.92x57mm ammunition
composite photograph of cartridge cut in half stood next to intact cartridge and base of cartridge
German 7.92 mm s.S. 12.8 g (198 gr) Full Metal Jacket Boat-Tail round.

200gr... They weren't screwing around.

They originally had a few different bullet weights and charges, they standardised a bit in the 1930's. The 198 grain round was originally meant only as a machine gun round. To get rid of so many variants they used the heavier projectile in rifles as well.

Most of my German rifles are WW! and are calibtrated for the 153 grainer, which is a far more pleasant round to fire..

As a general rule you are better to simply find a bullet you like, I would humbly suggest a 155 grain HDC Dyer, that groups well. Zero the front sight for 100 then simply find out where on the slide the other ranges are best set.

Just my humble opinions, keep it cheap and simple.

[horter]

200gr... They weren't screwing around.

I guess they're factoring in armor, building cover and the rest.

[Gregg]

200gr... They weren't screwing around.

Not being flip here but it wasn't a paintball match after all.

[fenderstrat]

Right, so I went to the range and confirmed it, about 13-14 in high. very good groups though. Getting a new blank front sight from brownells to fix the problem, we'll see how we go. Thanks a lot for your help guys!

[Chronos]

Right, so I went to the range and confirmed it, about 13-14 in high. very good groups though. Getting a new blank front sight from brownells to fix the problem, we'll see how we go. Thanks a lot for your help guys!

Sounds like that's the best route in the long run mate,

Chronos