Lapua .308 ammo

Hezz700

I bought some Lapua .308 200gr FMJBT subsonic recently but have not yet tried them out.

I checked out the twist requirements on lapua's website and the info given was as follows

Required twist: 1 turn in 250mm
Max barrell lenght: 450mm (this cannot be right???)

That would mean the barrell could be no greater than 17 3/4 inches in lenght

Has anyone used this stuff and if so how did you find them?

Will they stabilize with a twist of 1 in 280mm and 600mm barrell?

Any opinion welcome:)

Hezz

foxshooter243

Hezz700 wrote: »

I bought some Lapua .308 200gr FMJBT subsonic recently but have not yet tried them out.

I checked out the twist requirements on lapua's website and the info given was as follows

Required twist: 1 turn in 250mm
Max barrell lenght: 450mm (this cannot be right???)

That would mean the barrell could be no greater than 17 3/4 inches in lenght

Has anyone used this stuff and if so how did you find them?

Will they stabilize with a twist of 1 in 280mm and 600mm barrell?

Any opinion welcome:)

Hezz

Ive never used them but{im open to correction on this} subsonic ammo is only marginally stable at the best of times as the velocity is part of the stability equation, in the longer than specified barrel you will develop more velocity which will probably make the bullet supersonic instead of subsonic,tests have shown that one inch in barrel length equates to about
20 ft/sec in 308..in the states guys wishing to use subsonic ammo in 308 s are known to cut their barrels down, the twist that they specify is correct due to the low velocity etc but be aware of one thing hezz,take of your moderator before you try them! make sure they stabilise or bang goes your can! stay safe:D

Hezz700

Cheers F,

I hav'nt bought a moddy for her yet so nothing to be worried about there. Extensive studies will be carried out when i get the chance.

Hezz

Gunter Mauser

Hezz did you happen to get the price per 20 rounds of std Lapua Match
ammo in 308 in and around 168g.?

Hezz700

Sorry Gunter, i did,nt. i was actually looking for 168g but they had none in stock so i got the 200g subs instead. Just out of curiosity more than anything. it cost me 58 quid to satisfy said curosity:(

foxshooter243

Hezz700 wrote: »

Sorry Gunter, i did,nt. i was actually looking for 168g but they had none in stock so i got the 200g subs instead. Just out of curiosity more than anything. it cost me 58 quid to satisfy said curosity:(

curiosity killed the cat hezz:eek: but we all do it:D

Gunter Mauser

You will need to be loaded or win the lotto to shoot in this country

foxshooter243

Gunter Mauser wrote: »

You will need to be loaded or win the lotto to shoot in this country

not loaded Gunther, reloaded!:D

It wasn't me!

foxshooter243 wrote: »

not loaded Gunther, reloaded!:D

I was going to make that joke, then decided it'd lower the tone too much, good work

Sandy22

foxshooter243 wrote: »

... subsonic ammo is only marginally stable at the best of times ...

Gosh, don't tell those thousands of smallbore shooters who think Eley Tenex is the best ammo in the world.


You did say you were open to correction; well, I think you may be confusing subsonic and transonic.

Sparks

Sandy22 wrote: »

Gosh, don't tell those thousands of smallbore shooters who think Eley Tenex is the best ammo in the world.

Bleh. Never trusted Tenex after I had a round of it go through the target sideways in Rathdrum. Now if you'd said Lapua Midas or RWS R50...

(And why didn't anyone mention RWS R10 or H&N Finale Match? Pellets are ammunition too! )

IRLConor

Sandy22 wrote: »

Gosh, don't tell those thousands of smallbore shooters who think Eley Tenex is the best ammo in the world.


You did say you were open to correction; well, I think you may be confusing subsonic and transonic.

If I remember correctly, the problem is that when a bullet goes from supersonic to subsonic or the other way around the centre of pressure moves which can destabilise the bullet if it isn't damped. Even when it is damped, the movement caused by the "wobble" during the transonic phase will be hard to compensate for.

If the round stays supersonic or subsonic all the way to the target then it should be fine.

IRLConor

Sparks wrote: »

Bleh. Never trusted Tenex after I had a round of it go through the target sideways in Rathdrum. Now if you'd said Lapua Midas or RWS R50...

Meh, I've been using Eley Match EPS for the last while and it has kicked the pants off Lapua Master in DURC's Walther KK200 (it's cleaner too). I must try RWS R50 at some stage.

Sparks

Record that batch number Conor!

foxshooter243

Sandy22 wrote: »

Gosh, don't tell those thousands of smallbore shooters who think Eley Tenex is the best ammo in the world.


You did say you were open to correction; well, I think you may be confusing subsonic and transonic.

The ammo being discussed is advertised as being subsonic by the manufacturer, its not my definition, its supposed to be running at 1000 ft/sec, the difference between subsonic ammo in 22lr and 308 winchester
is bullet length at low velocity , the terminal effect that shooters using 308 winchester require is poor so to offset it they use heavy bullets-like
the 200 grain in the lapua round mentioned, so 1000 ft/sec along with short barrel to keep down velocity and 200 grain bullet= marginal stability.
The round is never supposed to be either transonic or supersonic its meant to be subsonic.assume a 1:12 -inch barrel firing a bullet at 1000 ft/sec-this equals 1000 rotations per/sec, at 2000 ft/sec the rotations per sec double, so the faster the spin the more stability we have, now if we were to reverse this we lessen our stability fair enough?now take a look at a 22lr bullet and a 200 grain lapua 308 round -theres a huge difference in length! now guess which one is easier stabilised at 1000 ft/sec, you cant compare them its like apples and oranges.

foxshooter243

Sparks wrote: »

Bleh. Never trusted Tenex after I had a round of it go through the target sideways in Rathdrum. Now if you'd said Lapua Midas or RWS R50...

(And why didn't anyone mention RWS R10 or H&N Finale Match? Pellets are ammunition too! )

you cant say that sparks cos that meant the round was unstable:eek::D

Sandy22

foxshooter243 wrote: »

The ammo being discussed is advertised as being subsonic by the manufacturer, its not my definition, its supposed to be running at 1000 ft/sec, the difference between subsonic ammo in 22lr and 308 winchester
is bullet length at low velocity , the terminal effect that shooters using 308 winchester require is poor so to offset it they use heavy bullets-like
the 200 grain in the lapua round mentioned, so 1000 ft/sec along with short barrel to keep down velocity and 200 grain bullet= marginal stability.
The round is never supposed to be either transonic or supersonic its meant to be subsonic.assume a 1:12 -inch barrel firing a bullet at 1000 ft/sec-this equals 1000 rotations per/sec, at 2000 ft/sec the rotations per sec double, so the faster the spin the more stability we have, now if we were to reverse this we lessen our stability fair enough?now take a look at a 22lr bullet and a 200 grain lapua 308 round -theres a huge difference in length! now guess which one is easier stabilised at 1000 ft/sec, you cant compare them its like apples and oranges.

O.k., now I understand what you mean. Your earlier post, on first reading, gave the impression you meant something else - my mistake.

I still wonder why they use that particular bullet - you'd think they could still get adequate terminal performance with a lighter, flat-based, maybe round-nosed bullet, which would presumably give a worthwhile improvement in stability if the 200 BT is marginal(?)

Incidentally your comparison metaphor isn't valid; the ballistic coefficients of apples and oranges are actually quite similar . Now pears & bananas................

foxshooter243

Sandy22 wrote: »

O.k., now I understand what you mean. Your earlier post, on first reading, gave the impression you meant something else - my mistake.

I still wonder why they use that particular bullet - you'd think they could still get adequate terminal performance with a lighter, flat-based, maybe round-nosed bullet, which would presumably give a worthwhile improvement in stability if the 200 BT is marginal(?)

Incidentally your comparison metaphor isn't valid; the ballistic coefficients of apples and oranges are actually quite similar . Now pears & bananas................

seems the reason they use the heavier bullets is because the subsonic ammo is tumbling very quickly on fleshy targets[ BROAD DESCRIPTION THERE:D] so they move up the weight for better terminal performance.
although i know that Lapua have developed a new bullet for this application but havent seen any results on it yet, but the b.c of a banana
would be hard to figure:D

It wasn't me!

On a mildly interesting note, was using Master tonight, and while some holes are incredibly clean, at least as clean as the Match EPS (seriously, looks like I punched it with paper, pity they're 9's anyway :P), some are nowhere near as clean. Anyone any idea what'd be causing the disparity in the holes formed?

Sandy22

It wasn't me! wrote: »

On a mildly interesting note, was using Master tonight, and while some holes are incredibly clean, at least as clean as the Match EPS (seriously, looks like I punched it with paper, pity they're 9's anyway :P), some are nowhere near as clean. Anyone any idea what'd be causing the disparity in the holes formed?

Paper quality?

It wasn't me!

Yeah, just odd that it'd be in the same card.

IRLConor

Possibly. We do have trouble keeping the targets dry in DURC, our range is quite damp. Although I know in like-for-like shooting Eley Match EPS makes neater holes than the cheaper ammo in DURC so it's not all paper quality.

ssl

SO HEZZ 700, did u shoot the lapau subs yet? Would they drop a buck at 200 quietly?

Kramer

ssl wrote: »

.......lapau subs......Would they drop a buck at 200 quietly?

It would be illegal to hunt deer in Ireland with that round, not to mention immoral - FMJ, underpowered etc.

ssl

Illegal, of course, stating the obvious there Kramer. Immoral, Is it not immoral to kill any living creature??? Joke.
Does anyone know how these rounds perform ,either on critters(fox etc) or a ballistic materail.
I think all owners of fully stocked rifles (who cannot fit moderators) would be interested in the results- penatration, damage, etc

bang2

ssl wrote: »

Illegal, of course, stating the obvious there Kramer. Immoral, Is it not immoral to kill any living creature??? Joke.
Does anyone know how these rounds perform ,either on critters(fox etc) or a ballistic materail.
I think all owners of fully stocked rifles (who cannot fit moderators) would be interested in the results- penatration, damage, etc

Not on animals or ballistic material
but on paper they hit the target 8 inches lower than federal fusion at 100m with a CZ550. moderated , very quiet.
not much help for fully stocked rifles ...

ssl

Cheers bang2. 6" is quite a drop.
Anything that reduces the bang off the rifle could be a help.
I'd like to see the results in a ballistics medium. Has anyone every made any?

demonloop

I've noticed at our club that Eley Match makes what looks like a bigger hole than Tenex. It looks bigger, but more accurate to say the Tenex hole has ragged paper pushed out towards the rear of the card, which naturally folds back in on itself, whereas the Match seems to remove all this extra raggedness round the rear of the shot hole.

Don't know if it means anything though

intershoot

demonloop wrote: »

I've noticed at our club that Eley Match makes what looks like a bigger hole than Tenex. It looks bigger, but more accurate to say the Tenex hole has ragged paper pushed out towards the rear of the card, which naturally folds back in on itself, whereas the Match seems to remove all this extra raggedness round the rear of the shot hole.

Don't know if it means anything though

It means your still depending on the tears to touch the 9-ring again....arnt ya!! :rolleyes:

They are both the same bloody round, so how the hell are they gonna give you a different hole size ye numpty. Lookin at that screen from the perch is probably affecting yer eyes!

Maybe that new gun is letting them turn in the barrel and they're goin in backwards! or yer just creating a smoke screen for the cards yer punching for the league.