Printable View
The rear sight of my new L1A1 jumps forward whilst firing, presumably due to the re-coil.
Has anyone else experienced this?
Peter has suggested that I need to hold it into my shoulder more firmly (!). True, I could do with a size larger Butt Plate.
Another suggestion is that the rifle might be giving a more powerful recoil now that the gas operating system etc have been removed.
Charlie
Look at it logically........... The sight can ONLY move forwards if a) you push it forwards against the spring and balls in the detents or b) the rifle moves back pretty sharpish, in effect leaving anything moveable - such as the backsight slide and leaf - to remain where it is as the rifle moves back. There is NOTHING else. You can tie the backsight slide and leaf down with some string or sticky tape or you can replace the ball and spring. The acid test is to hold the rifle butt first, against a solid brick wall and fire it. If the slide doesn't moive forwards then, then it's operator error! It is nothing to do with lack of gas because............ it's going to get technical now so I'll stop!
Tuck it into the shoulder hard, get the sight picture........ man laying at the edge of the hedge............hold...........tight, slightly exhale....... squeeeeeeeeeeze the trigger and bang. Target falls when hit. Backsight remains upright and at the set range
I think the first thing to try is :-
Try moving the backsight up and down the ramp, if it move easily there is a serious problem.
A backsight that has its Ball and Detent correctly fitted (or fitted at all) will require substantial pressure to get it to change position up or down.
How easily can you move your backsight?
The backsight is quite difficult to move, as one would expect. I've tried 2 now, both exactly the same, as Peter says, must be the other variable - me!
Quote:
Originally Posted by Charlie303
Well, that must be three of us at least so far, that cannot shoot ;) - or it's Newton's Third Law of Motion ;)
Mine does it too, and someone else mentioned their also does it (Oxford Andy or Daryl, IIRC) - EDIT - checked my PM's, it was Daryl.
First time out with it, whilst trying to zero at 100 yards mine shot up from 200 to 600 every shot....except I didn't notice until I was on the 300 yard mark :rolleyes:
Mine also kicks like hell (it was pulled VERY tight in my shoulder, and I still had a 4" square bruise next day), and removal of the gas recoil mechanism MUST have something to do with that.
I also have wood furniture and an ally butt plate on mine - no give anywhere, except my shoulder.
What ammo are you using - is it pokey stuff?
I've got a new sight/detent spring/ball for mine, but haven't bothered fitting it yet as I have scoped it now.
Still love the rifle though :D :madsmile:
My L1A1 did the same thing. Not every time just when I wasn't watching for it to do it. I would look up and it would be moved. The bad thing was it was real hard to move back. Now I have it tied back with a small black nylon slip tie. You don't even notice it, but I know it's there. Just looks kind of cheep, but I guess I can live with it. I'm glad to know it just wasn't only mine that moved. I've been watching these fourms for a few years to see if anybody else had the same problem as me. YES finely!!!!!!
I wouldn't bother messing about with the rear sight. I've tried 2 and Peter gave me a new spring and some new balls (no comments please). Although I haven't tried the new ones whilst firing yet, they all measure exactly the same, the backsight feels the same when being adjusted. I just don't think there's anything wrong there.
I'm using Privi .308. The rifle is as bought (plastic furniture) and I get an average kick, much as with a .303 No.4 and not as much as the No.5.
The fact is, even if well tucked in, there's still going to be an immediate backwards movement, even if it's not a great distance. My shoulder is muscle, bones and tendons, it's not a brick wall.
I think that it's significant if 3 of us are getting the same effect with a new rifle. The dynamics between the old 7.62mm L1A1 gas operated SLR and new .308 L1A1 'bolt action' have altered something.
I just scraped a pass in O level physics and I wouldn't dare argue with Peter on this, but if the energy that previously knocked back the breech block, carrier, hammer, return springs isn't being used, it surely must be going somewhere?
---------- Post added at 06:15 PM ---------- Previous post was at 06:13 PM ----------
Karr66,
Not sure where you are, so is your L1A1 gas operated or like ours in the UK, bolt action?
Charlie
Charlie
I'm also using PRVI. The L1A1 recoils more than my Enfield .303 No 4 Mk II.
It must be something to do with the removal of the gas mechanism. Not only does Newton's Third Law come into play, but weight is physically removed from the rifles by way of the deleted gas components, and that can't help.
That wasn't a criticism of Peter in my previous post by the way, he's forgotten more about these rifles than I will ever learn!
I suspect .308 ammo has more powder behind it than the milspec 7.62 - I keep meaning to check, but keep forgetting :rolleyes:
In comparison, my deer stalking rifle is a .308 CZ 550 - 26" heavy barrel, laminate stock, it weighs a ton, and it's a pussycat to shoot :)
From the posting style, my bet would be that Kar66 is from the USA :)
My further guess would be that he has a Century or DSA kit based L1A1 ;)
Maybe someone ought to try using bog standard UK Milspec NATO ball.
Regarding the loss of the gas system, it could get complicated so I'll keep it simple. The gas vent is all tied up with Boyles law and you need to remember that the mechanical safety ensures that the bullet has already left the bore and 2 metres down the range and the gas in the barrel has been reduced to atmospheric pressure before the breech block has even commenced to unlock and that is on a standard L1A1. Yours haven't even got that. It's also worth remembering that on the old L1A1, recoil had already taken place by the time the breech block unlocks. What I am saying is that the amount of extra gas and therefore muzzle velocity and recoil available to your rifles WITHOUT a gas port compared to the standard L1A1's WITH the gas facility, is absolutely unnoticeably minimal. It would take very accurate and calibrated measuring equipment to discern the difference. I know this because we did similar trials and tests with AK47's (Ok, ok, I know it's not exactly like for like........) But when we did other trials with doctored L1A1's at Shrivenham, the m/v differentials were so slight that they could be put down to ammunition variables. Also, it's worth bearing in mind that we COULD disconnect the gas system of our L1A1's by rotating the gas plugs. And shooting them like that didn't move the backsight slide upwards.
Nope.......... I'd like to suggest using bog standard RG NATO ball for a start and then on the Enfield layer in the test range in order to eliminate the human factor
Peter
The ACR L1A1's are rechambered in .308, and hard extract with 7.62 ammo, so we can't use that.
The NATO spec 7.62x51 ammo appears to be in the 147 to 150 grain bullet range. The PRVI is 175 grains. I plan to step back to their 145 grain load when I buy the next batch (I've still got 190 rounds of 175 to use........:o ).
I take your point re the gas recoil mechanism. I said you had forgotten more than I know on these rifles :D
I must put mine on the scales to see what it weighs, compared to the original spec.
If you weren't quite so far away i'd let you shoot mine to see what you think.......:)
I haven't bothered doing anything with my jumping rear sight because the SLR is scoped so it didn't matter.
However, I am contemplating using it with open sights so decided a bit of amateur gunsmithing was in order (I can hear Peter L shuddering from here :lol: ).
I stripped the Hythe sight I got, put a new detent ball and spring in (yes Peter, I did take your advice and do it inside a clear plastic bag ;), and thank you again for the new spring and ball you sent me), and put that on. Someone on FalFiles gave me the tip of only take one windage adjuster screw out, so you don't lose your windage setting.
It was an easy job, only took a few minutes.
When I first used it with open sights, not only was the rear aperture like peering through the Dartford Tunnel, but the front sight blade is so thick that it was covering the whole of the scoring area of a 600 yard target! :eek:
I had got a spare front sight blade for this purpose, so I took it out and carefully ground it down equally either side on the bench grinder to about half of its previous thickness (it's now approximately the same thickness as my No 4 Mk II front blade).
Hopefully out with it at STANTA next Thursday, i'll whip the scope off and see what it shoots like with the new irons on :madsmile:
I was on the STANTA Great Carr MoD battle training area today, put 117 rounds through the L1A1, and the Hythe sight didn't move once. Cured. Thanks to Peter L and others for their guidance/parts kindly donated :)
Hi David,
Glad to see that the rear sight is sorted, taking mine, which now has the wood installed, to Bisley tomorrow to try at 300 and 500. Will have another go with the Trilux to see if i can get on with it before I fit a bullet drop compensated scope.
Have fitted a bipod stud to the forend wood which is from Ironwood in the States and is much sturdier than the original, I think the rifle will be much easier to handle from a bipod, won't have to break the rest from the left hand to reload. Trying out some Privi 145grn and some reloads with Lapua 155grn.
Will give a report next week and some pics.
Well had a great shoot at Bisley on Sunday, rain came down at lunchtime but cleard up afterwards.
At 300yrds the L1A1 performed well, I was shooting homeloads which sometimes failed to chamber, I think they need to be full length resized,I'd only neck sized them. I also shot some Privi 145grn loads, they cycled well and shot to sights.
My friend had some new Lithuanian 7.62 nato, that the range office is now selling. i thought i'd try a round expecting it to have hard extraction, but it was fine, tried another 20 and they all cycled well, so have found a source of milsurp that works in the straight pull. Result at £55/100!
As far as sights, the bipod setup seemed to to make recoil very controlable even with a wood butt, and the rear sight did not move at all.still find it difficult to focus on the front sight, and the large rear aperture is difficult to centre. still held the black at 300 and 500. The Trilux was fine at 300, but at 500 the point of impact shifted every 5 rounds or so, can only assume the mount/cam were moving, the whole setup has some movement and is not solid, maybe the springs are past there best.
Will mount a 'proper' scope when I get the DSA mount from thr States, which is taking ages.
All in all very happy with the setup, created a lot of interest with the HBSA crowd, though they weren't sure about the bipod,and have been offered a hythe sight!
Daryl
Glad to hear it went well.
Mine got a bit tight at one point last week (PRVI 175gn rounds), but I was snap shooting at Figure 12 targets and put 30 rounds through it in about 3 minutes, the barrel was red hot, so that's hardly surprising :eek:
The Hythe sight is worth fitting because of the smaller day rear leaf aperture. Bench grinding my front sight blade down by about half the thickness (to about an Enfield No 4 Mk II size) worked too. Get a spare blade to practice on!
I have to say, having tried both (and I didn't think i'd say this), I think it is more fun to shoot with open sights.
I've got some PRVI 145gn on order which hopefully will be kinder to the shoulder!
Not fired mine yet, I will be using my suit sight mainly, but will be using irons too, seeing as 3 of us ? have the same rifles be interesting to see what the resolve is.Quote:
Originally Posted by Charlie303
If anyone is looking for the DS Arms top cover with scope rail, Brownells will ship to the UK and normally have them in stock.
http://www.brownells.com
Attachment 26685Attachment 26686
Pics of my L1A1 with wood. butt is original extra long, forend is Ironwood repro.
Both beech, the Ironwood is much thicker than original, so I could inlet a Harris 2R bipod stud through one of the cooling holes. Works fine, recoil doesn@t spring the wood, and it can be removed without showing.
Nice wood, now get the pistol grip and carry handle fitted :madsmile:Quote:
Originally Posted by daryldiane
LOVELY wood
This one was doing the same thing until I snugged up the fit of the sight rail engagement with the base block.
https://www.milsurps.com/vbpgimage.p...5&d=1261418590