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Skeeter60
10-09-2009, 01:56 PM
A rifle needs to be accurised before expecting it to perform well ie put 5 shots regularly in 1.5 inches or lesser at 100 yds.
Most quality rifles will do it but would still be prone to shifting zeroe with the change in weather.
Following work has to be done.

FREE FLOATING the BARREL
Ensure the barrel ; from 1 to 2inches ahead of where the receiver ends, does not touch the stock. You are able to slide a paper under the barrel between the stock just short of the receiver. This can be done by a gun smith who can deepen and slightly widen the barrel channel of the stock.

Glass Bedding the Action.

The action should be bedded in steel epoxy. The method of glass bedding is given with complete instructions and pictures on the net so please follow those instructions.
This will ensure your rifle will not change zero what ever weather changes occur. The stock wood shrinks and expands with changes in humidity and temperature exerting pressure on the action and the barrel, thus shifting zeroe.

The trigger should have a crisp let off at about three pounds ( less than that will lead to accidental discharges and poor trigger control in hunting)

Muzzle Crowning
The muzzle should be crowned to 11 degrees as we mostly use boat tailed bullets and the rifles come with a 45 degree crown. The 11 degree suits th BT bullets.

Once these things are done your rifle will be ready to shoot accurately without shifting zeroe what ever the weather conditions.

hasnaincfa
10-09-2009, 03:14 PM
Nice inf0 br0ther.

Zubair
10-09-2009, 03:24 PM
Good info...too bad all of them now require a PB license

Denovo87
10-09-2009, 03:48 PM
Thanks Skeeter, thats the info we cannot get anywhere else from, you are an asset of the PG family.

MIdreesTaj
10-09-2009, 06:02 PM
@Skeeter60 sb,

Plz shed some light on the subject of muzzle crown protection and its important.
+
Polygonal rifling, not in greater details bcuz its gonna be too much for little space available here.. :) only let us know how it compares to a conventional rifling regarding accuracy of a rifle. thanks

KageFox
10-09-2009, 06:03 PM
Very informative, sir.

A query: You mention in the glass bedding part that a wandering zero is contributed by the changes in the wood stock (due to weather). Will replacing the same stock by a polymer one offer the same benefits as glass bedding, as polymer (to my knowledge) reacts less to changes in temperature and humidity?

Skeeter60
10-09-2009, 06:15 PM
Kagefox wrote You mention in the glass bedding part that a wandering zero is contributed by the changes in the wood stock (due to weather). Will replacing the same stock by a polymer one offer the same benefits as glass bedding, as polymer (to my knowledge) reacts less to changes in temperature and humidity?

Yes the polymer stocks are more stable specially if of good quality, but it is extremely important to glass bed a polymer stock; if this is not done these are prone to cracking and splitting. The full accuracy potential will also be achieved after glass bedding.

Skeeter60
10-09-2009, 06:36 PM
midreestaj wrote
Plz shed some light on the subject of muzzle crown protection and its important.
+
Polygonal rifling, not in greater details bcuz its gonna be too much for little space available here.. smile only let us know how it compares to a conventional rifling regarding accuracy of a rifle. thanks

The crown is extremely important it protects the rifling from dings and burrs while hunting. It is ruined by two things if improperly done. CHORD WEAR and ROD WEAR.
Never pull, a pull through from the Muzzle, always insert from the muzzle and pull from the breach/chamber side

Always remove the bolt and insert the rod from the chamber side. If you do reverse of this you can destroy the accuracy potential of a rifle in few careless cleanings. The chord and rod both cause wear on a particular place allowing gas to escape pushing the base of the bullet and causing further erosion of the muzzle . When a hard surface is rubbed on a soft surface it is the hard surface which gets eroded if there are unburnt powder particles which are abrasive. Look at sand paper it wears out steel when rubbed against it as abrasive material sticks to soft material.

Polygonal Rifling

The first ever rifling was polygonal. The German H&K uses it for rifles so does Glock. For Sniper Rifles this is not the preferred type of rifling as though it helps in getting higher velocities from pistol and rifle barrels it causes more mutilation of the bullet surface and is not good for extreme accuracy. The H&K PSG1 uses it but it is not as accurate at longer ranges as other modern comparable rifles.
I hope I did justice to your question. Regards

MIdreesTaj
10-09-2009, 06:49 PM
@Skeeter60
Thanks alot Sir! We all clean our weapons and we all appreciate the wahtever inherent accuracy of our beloved weapons... So there it is...this information is a must know sort of...

About PSG1, cold hammer forged polygonal rifled barrel.. HnK says it will put 50 rounds in 10cm of width at 300m. You said, its not as accurate as other comparable rifles... do you really think it doesnt compare accuracy wise to other semi-automatic snipers like may be ?SIG SSG mods...? I always had a high esteem of PSG1 regarding its semi-auto accuracy out of the box...

Skeeter60
10-09-2009, 07:14 PM
midrees taj

The first sniper rifles with the SSG prior to the Steyr SSG 69 ( SSG stands for (sharp Steutzen Gehwere ) I hope I did not mess the spellings my german is not good(not SIG )
It means sharp shooters rifle
I have tried it, it is not as accurate as thought by many people. No wonder Pak army has moved to the SSG 69, the Mcmillan ,Barrett and of course the Accuracy International.
No semi auto can be as accurate as a Bolt action all things being equal.
The PSG is too heavy too long and not accurate beyond 300. You mentioned 20 shots in 10 cms at 300 well it is not good The accuracy International would group 20 shots in a cluster of hardly 4 to 5cms at 300 m with Norma Diamond line 168 grs or the Winchester/Nosler J4 168 gr bullet

KageFox
10-09-2009, 07:15 PM
Is the HK PSG1 over-rated? I mean, its pretty rare and expensive and it is one of the few semi-auto sniper rifles, though more are cropping up these days...

And is a PSG1 clone made in Pakistan? 'Cuz Wiki lists our country as users of the PSG1...

Skeeter60
10-09-2009, 07:52 PM
Kagefox
It was never made in Pakistan but was in use more than 25 years ago. It is good upto 300m and not more. I must add it was the Sniper Rifle of choice in the Urban Sniper Role where quick shots at ranges of under two hundred or so yards are required. Over the years how ever many other rifles (Semi-auto) have taken over like the accurised AR 15 which is virtually recoilless and one can shoot very fast two or more rds.

Dr Zakir
10-09-2009, 08:03 PM
sir very professional information . i would like to know few things one is if you buy a rifle old or nib you have to go for above process.
what do you think about 3006 calibre as compared to 7.62 * 51 and what are your comments on dragnov rifle as compared to others
thankyou

Skeeter60
10-09-2009, 08:37 PM
Dr Zakir
It is good for both new and old rifles, it will make them more accurate and your zeroe will not wander.
Now the 30-06 is a faster 7.62x51, much faster if you reload or use Hornady Light Magnum ammo. The 7.62x 51 has more accuracy potential though.
The third question . The Dragunov Semi Auto Sniper Rifle. Well there is no comparison at all, any good western US or German or Austrian hunting rifle is far more accurate then this Dragunov . Also the scope is not replaceable easily you have to stick with the same contraption. The Americans now laugh at it but before the Russians came up with their excellent Bolt Sniper Rifle they were singing praises for it so the Russians do not improve it, like the T72 tanks which lost there Turrets when hit.
I might be stepping on the toes of those friends who possess the Dragonuv and swear by its accuracy, but this is my opinion after having used it extensively. It groups around 2 1/2 in at a 100 yds and about 7 inches at 300 yds when at its best. It does shoot smaller and very large groups so I am talking of the average

MIdreesTaj
10-09-2009, 08:48 PM
@Skeeter60
Sir plz some insight to Weatherby rifles.. ?
I think they are very superior family of hunting, varmint and safari rifles..
Their Mark 5's specially...
Your comments awaited!

MIdreesTaj
10-09-2009, 08:53 PM
7.62x 51
a universal sniping round....

for more range and knockdown...
step up to 300 winmag and
338 lapua mag...

Skeeter60
10-09-2009, 09:00 PM
Weatherby Mk 5 rifles have one of the safest and strongest actions in the world, though a bit heavy. These are good to look at although the traditionalists do not approve of the flashy stock the white spacers and the basket weave chekering. These are accurate and fast some calibers are hits like the .416 and the .300, and .257. The others are also there with the 7mm being a little popular the others are not very popular.
I have a .460 weatherby Mag Mk V deluxe. The 270 wby is known for less Bbl life, the 378 is not popular so on and so forth.

Skeeter60
10-09-2009, 09:20 PM
midreestaj
weatherby rifles or any other are less popular for safari when hunting dangerous game. Only the Mauser 98 based actions rule supreme. Like the Mauser, the Brno and Winchester Model 70 (pre 64 action) and a large number of custom rifles with the one essential; the action has to be based on the grand Mauser M98 (made in 1898 by that grand inventor Paul Mauser) Before you ask me why it is because of the controlled feed and non rotating claw extractor. You will only trust this action when you face a buffaloe

MIdreesTaj
10-09-2009, 09:28 PM
@Skeeter60
Sir heard alot about Mauser Actions... it commands on bolt-actions like J.brownings short recoil cam-lock system does on semiauto pistols.
Thanks alot for proving time and valuable information...

HasanJamshad
10-09-2009, 09:53 PM
Sir, why do we prefer controlled feed over pushed feed while most of the guns come with pushed feed function.

Skeeter60
11-09-2009, 12:15 AM
Sir, why do we prefer controlled feed over pushed feed while most of the guns come with pushed feed function.

Dear HJ
The controlled feed extractor gets hold of the cartridge before feeding and whether you are running diving or ducking the round will feed. The main advantage is that the claw extractor will never slip over the rim of the cartridge. It happens when there is dirt in the chamber, the round is over pressure or the chamber or the cartridge case have a defect being out of round, all these things happen in real life,if the fired case does not extract and eject you have the mother of all double feeds. When an angry buffaloe is looking at you as if you owe him money and charging at you the Murphies laws take over.
If any thing can go wrong; it will. At a time it hurts most.

Brother you do not want Mr. Murphy's Law to hold true when confronted with a buffaloe, an elephant, a lion, a Rhino or leopard. May be most of these will change their minds but never a Buffaloe .
The controlled feed is also extremely reliable at extraction and ejection. The push feed types are fairly good at feeding but extraction can be dicy under adverse conditions. No one wants to take a chance with dangerous game

MHMalik
11-09-2009, 01:09 AM
Since we are discussing rifles of this nature I would like the esteemed members views on using AR10 as a sharpshooting platform. Any thoughts?

HasanJamshad
11-09-2009, 10:21 AM
@skeeter60, sir thank you very much for explaining now i got it. You can expect such questions from the people like me who have experience with range toys and have never been into the kind of shooting where oponent can be other than a paper target. :)

Gunfire
11-09-2009, 02:33 PM
@Skeeter60 sir,
I have come across a De-Resonator for controlling the vibrations and barrel jump in rifles that cause discomfort & inaccuracy. Does a De-Resonator make a big difference?

Malik1
11-09-2009, 03:38 PM
Sir! Extremely professional and knowledgeable input. Thank you very much for sharing these infos

Dr Zakir
11-09-2009, 07:04 PM
Thankyou sir for very precise and informative reply . I would like to suggest me which rifle should I buy . I already have a brono .22 and now I am interested in a big bore rifle

Skeeter60
11-09-2009, 07:41 PM
Dr Zakir

I am still proud of my brno I got when I was 12. It is a great rifle,very accurate.
So you want to buy a big bore, I think go with a .308 Win, a 30-06 or a .270 . I like 7mm Rem Mag, 30-06 and .308 cals
Find a carefully used Winchester Mod 70 (pre 64) or a Rem 700 BDL , new Rifles are not available but you can easily find rifles which are hardly used. Steyrs and Browning A bolts are also available all are fine rifles. The condition must be A I .

Skeeter60
15-09-2009, 12:27 PM
@Skeeter60 sir,
I have come across a De-Resonator for controlling the vibrations and barrel jump in rifles that cause discomfort & inaccuracy. Does a De-Resonator make a big difference?

Dear Gunfire,
Regret overlooking your question saw it today.
When a Rifle is fired its barrel vibrates like a tuning fork, this enlarges the groups fired. A De-Resonator does not time the departure of the bullet in the middle of vibrations but on one extreme end; thereby shrinking the dispersion of the group.
Incedently only very accurate rifles benefit from it.
A sweet spot is found during firing (by rotating an indexed dial/weight attached at the muzzle end by trial and error)
These help reduce group sizes of Bench Rest Rifles to 1/10th of an inch or so at a 100yds. These are only for Bench Rest Rifles usually .22.
These are made by Gun smiths like Hohen, you can find his address on the net. I hope I spelt his name right

Skeeter60
15-09-2009, 12:30 PM
@Skeeter60 sir,
I have come across a De-Resonator for controlling the vibrations and barrel jump in rifles that cause discomfort & inaccuracy. Does a De-Resonator make a big difference?

Dear Gunfire,
Regret overlooking your question saw it today.
When a Rifle is fired its barrel vibrates like a tuning fork, this enlarges the groups fired. A De-Resonator does not time the departure of the bullet in the middle of vibrations but on one extreme end; thereby shrinking the dispersion of the group.
Incedently only very accurate rifles benefit from it.
A sweet spot is found during firing (by rotating an indexed dial/weight attached at the muzzle end by trial and error)
These help reduce group sizes of Bench Rest Rifles to 1/10th of an inch or so at a 100yds. These are only for Bench Rest Rifles usually .22.
These are made by Gun smiths like Hohen, you can find his address on the net. I hope I spelt his name right.
I want to add it does nothing to the shooting comfort or discomfort .
Also some friends will ask how does one measure a group of 1/10 inch. Well you take the extreme spread of the group edge to edge and then substract caliber.

MUSTANIR
15-09-2009, 05:46 PM
Its been a long time since I read some really good n interesting stuff..
tnx buddies.

Gunfire
15-09-2009, 09:28 PM
thank you so much for the info...