EXTREME PRODUCTIONS’ GUN REVIEW #3: PRE-BAN AR-15 W/ NIKON 3-9X SCOPE
**** GUN REVIEW OVERVIEW ****
1.DESCRIPTION OF AR-15 TESTED
2. 50, 100, 225, 300 YARD FIRING TESTS
3. HIGH LOSS/BREAKAGE AR-15 PARTS
4. LUBRICATION ENHANCEMENT
5. DIRECTORY OF ON-LINE PHOTOGRAPHS. (All pictures associated with Gun Review #3 can presently be viewed at CAR-15 REVIEW PICTURES
A used pre-ban AR-15 rifle with Nikon 3-9x50mm scope was tested for accuracy at 50, 100, 225, and 300 yards using 40 and 50 gr. Moly-coated plastic-tip ammo, Israeli SS-109 63 gr. ammo, and South African 55 gr military ammo.
** PRE-BAN AR-15 RIFLE **
CALIBER: .223 (5.56 x 45 mm)
BARREL TWIST: 1:9
BARREL LENGTH: 16 INCHES
NON-REMOVABLE CARRY HANDLE SCOPE PLATFORM
TRIGGER: NON-ADJUSTABLE SINGLE STAGE
TRIGGER PULL: 6-7 lb.
SCOPE: NIKON 3-9x50 (special edition Buckmasters #6435)
SCOPE MOUNT: B-SQUARE AR-15 CARRY HANDLE "SEE THROUGH" SCOPE MOUNT (#18526)
SIGHT ENHANCEMENT: GLUED A BUBBLE LEVEL TO THE SCOPE’S ELEVATION ADJUSTMENT COVER.
******************* DESCRIPTION OF THE USED PRE-BAN AR-15 TESTED *******************
A used pre-ban AR-15 rifle with Nikon 3-9x50mm scope was tested for accuracy at 50, 100, and 225 yards.
The AR-15 barrel is 16 inches long and has a 1:9 twist. Nikon’s special edition Buckmasters 3-9x50 (#6435) scope was mounted to the AR-15’s non-removable carry handle via a B-Square Carry Handle "See Through" Mount (#18526).
**************************** 50, 100, 225 & 300 YARD FIRING TESTS ***************************
1. CONDITIONS: Barometric Pressure: 31.0 In. Hg.; Temp.: 55-60 F, Relative Humidity: 65%, Crosswind: 0-1 MPH
2. AMMO USED: (PICTURE 4)
**MILITARY**
ISRAELI SS-109 63 gr. FMJ ammo (5.56 MM, M855)
SOUTH AFRICAN 55 gr. FMJ ammo (5.56 x 45mm BALL M1A3 [263 A/85Z])
**HUNTING**
HORNADY 55 gr. VARMINT EXPRESS MOLY-COATED PLASTIC-TIP AMMO
HORNADY 40 gr. VARMINT EXPRESS MOLY-COATED PLASTIC-TIP AMMO
Pictures of the 10 targets can presently be viewed on-line at WWW.CARLIVING.NET/SHARON.HTM . The target pictures are numbered from T1 to T10. Each target has a low and high resolution picture. For example, target 1 has a picture with the name T1L (low resolution) and another named T1H (high resolution). A list of the on-line pictures is provided on the last page of this review.
A few adjustment were made to the Nikon 3-9 power scope during the shooting test. After shooting target one, the scope had to be re-mounted 180 degrees on the B-Square scope mount to allow for more eye relief. The scope was zeroed on the 50 yard target’s bulls-eye and then again on the 100 yard target’s bulls-eye. The B-Square scope mount’s mounting nut, the hand nut that holds the mount to the AR-15 carry handle, often needed tightening after firing 20 or so rounds; however, after adding a handmade fiber washer to the scope mount’s thumb screw/nut, the thumb screw remained fairly secure.
All targets were shot from a Protektor mechanical rest with two sand bags (picture 2). Except after shooting target 1, the AR-15 wasn’t cleaned during the rest of the shooting test. For all targets the point of aim was the center red bulls-eye.
**** 5-SHOT GROUP 50 YARD TARGET ****
** 50 YARD TARGET (T1) **
After initially mounting the Nikon scope, to sight in the scope, a 50 yard target (T1) was shot with Remington UMC 55 gr. FMJ .223 ammo from a Protektor mechanical rest and sand bags (picture 2). The rest wasn’t rigidly mounted to prevent movement. The scope was probably set to 6-7X power.
The five bullets landed an average of 5-1/4" above the target’s 1-3/4" diameter red center bulls-eye. Bullet speed was between 2801 to 2821 fps. The 2-shot group measured 1/4"; 3-shot group measured 9/16"; the 4-shot group measured 1-1/4"; and a 5-shot group of 2-1/4". The group was adequate considering that the shooting rest wasn’t rigidly mounted and that there was only about a 5 second delay between shots.
Since the eye relief wasn’t adequate, after shooting target 1 the scope was remounted 180 degrees in the B-Square mount, which turned the B-Square scope mount around placing the scope further away from the shooter.
**** 5-SHOT GROUP 100 YARD TARGETS (2ND SHOOTING SESSION) ****
** 100 YARD TARGETS 2, 3, and 4 (T2, T3, and T4) **
100 yard target 2 (T2) was shot with Hornady 55 gr. V-Max ammo. The scope’s power setting was somewhere between 6-7x. The time between shots was 10-20 seconds. Bullet speed was between 2767 and 2785 fps. Because the newly mounted scope hadn’t been adjusted, the bullets landed an average of 4 inches high and 4 inches to the right of the bulls-eye. The 2-shot group measured 1/16"; 3-shot group measured 1-3/4"; 4-shot group measured 3-5/8"; 5-shot group measured 4". Had a rigidly mounted shooting rest been used, a cool down period of 1 minute between shots allowed for, and the scope’s power setting set to 9x----I feel the 5-shot group would measure around 1-1/4 inch.
100 yard target 3 (T3) was shot with Hornady 40 gr. V-Max ammo. The scope’s power setting was somewhere between 6-7x. The time between shots was 10-20 seconds. Bullet speed was between 3227 and 3278 fps. The scope’s reticle still hadn’t been dialed in on the target’s bulls-eye; the bullets landed an average of 4 inches high and 4 inches to the right of the bulls-eye. 2-shot group measured 1/8"; 3-shot group of 1-1/8"; 4-shot group of 1-5/8"; 5-shot group of 2-5/8". Had a rigidly mounted shooting rest and 2-stage trigger been used, along with allowing for a full 1 minute cool down period between shots, I feel the 5-shot group could have measured around 3/4 inch with this ammo.
100 yard target 4 (T4) was shot with Hornady 55 gr. V-Max ammo. The Nikon scope was finally set on its 9x power setting. The time between shots was 1 minute. Bullet speed was between 2765 and 2847 fps. After firing the first shot, which landed 4 inches high and 4 inches to the right of the bulls-eye, the reticle adjustments were dialed 16 clicks to the left and 16 clicks down (1/4 MOA adjusters). Next, the 2-shot group measured 1/8"; 3-shot group measured15/16"; 4-shot group measured 1-3/8"; and the 5-shot group measured 1-3/4". One of the holes making up this 5-shot group came from a recoil fire, which occurred when my grip loosened on the AR-15 pistol grip. Had a rigidly mounted shooting rest and 2-stage trigger been used, along with allowing for a full 1 minute cool down period between shots, I feel the 5-shot group could have measured near 3/4 inch with this ammo.
100 yard target 5 (T5) was shot with Israeli SS-109 63 gr. FMJ .223 ammo. The Nikon scope was set at 9x. The time between shots was 1 minute. Bullet speed was between 2825 and 2856 fps. The 2-shot group measured 3/16", the 3-shot group measured 7/8"; the 4-shot group measured 1-1/4"; and the 5-shot group measured 1-3/4". Had a rigidly mounted shooting rest and a 2-stage trigger been used, along with allowing for a 2 minute rest period between shots, I feel the 5-shot group spread could have measured around 3/4 inch with this ammo. After shooting target 5, the B-Square scope mount’s gun attachment nut needed to be hand tightened.
100 yard target 6 (T6) was shot with South African 55 gr. FMJ .223 ammo. The Nikon scope was set to 9x power. The time between shots was 10-20 seconds. Bullet speed was between 2884 and 3024 fps. A 2-shot group measured 1/4", the 3-shot group measured 2"; the 4-shot group measured 2-3/8"; and the 5-shot group measured 3-15/16". One of the holes making up the 5-shot group came from a recoil fire, which occurred when my grip loosened on the AR-15 pistol grip. Had a rigidly mounted shooting rest and a 2-stage trigger been used, along with allowing for a full 1 minute cool down period between shots, I feel the 5-shot group could have measured around 2 inch with this ammo.
** 225 YARD TARGETS 7 - 10 **
225 yard target 7 (T7) was mistakenly shot with Hornady V-Max 55 gr. Moly coated plastic-tip ammo (meant to shoot 40 gr. V-Max). The Nikon scope was at 9x power. The time between shots was probably 45-60 seconds. Bullet speed was between 2748 and 2830 fps. A 2-shot group measured 27/32", the 3-shot group measured 2"; the 4-shot group measured 3-7/16"; and the 5-shot group measured 5-1/4". Had a rigidly mounted shooting rest, a 2-stage trigger, and a higher power scope been used, along with allowing for a full 2 minutes between shots, I feel the 5-shot group could have measured around 1-1/2 inches with this ammo.
225 yard target 8 (T8) was again shot with Hornady V-Max 55 gr. Moly coated plastic-tip ammo. The Nikon scope was at 9x power. The time between shots was probably 45-60 seconds. Bullet speed was between 2705 and 2830 fps. A 2-shot group measured 15/32", the 3-shot group measured 2-1/8"; the 4-shot group measured 3-11/32"; and the 5-shot group measured 5-1/8". Had a rigidly mounted shooting rest, a 2-stage trigger, a higher power scope been used and the copper fouling removed from the barrel before shooting, I feel the 5-shot group could have measured close to 1-1/2 inches with this ammo.
225 yard target 9 (T9) was shot with Israeli 63 gr. SS-109 FMJ ammo. The Nikon scope was at 9x power. The time between shots was probably 30-45 seconds. Bullet speed was between 2828 and 2869 fps. A 2-shot group measured 1-1/4", the 3-shot group measured 1-1/2"; the 4-shot group measured 3-26/32"; and the 5-shot group measured 7-1/4". One of the holes making up the 5-shot group came from a recoil fire, which occurred when my grip loosened on the AR-15 pistol grip. Had a rigidly mounted shooting rest, a 2-stage trigger, and a higher power scope been used along with allowing for a full two minutes between shot, I feel the 5-shot group could have been around 2 inches.
225 yard target 10 (T10) was shot with South African 55 gr. FMJ ammo. The Nikon scope was at 9x power. The time between shots was probably 30-45 seconds. Bullet speed was between 2905 and 2989 fps. A 2-shot group measured 1-1/4", the 3-shot group measured 1-1/2"; the 4-shot group measured 3-26/32"; and the 5-shot group measured 7-1/4". One of the holes making up the 5-shot group came from a recoil fire, which occurred when my grip loosened on the AR-15 pistol grip. Had a rigidly mounted shooting rest, a 2-stage trigger, and a higher power scope been used along with allowing a full 2 minute cool down period between shots, I feel the 5-shot spread could have been around 4 inches with this ammo.
** BULLET SPEED MEASUREMENTS FOR PRECEDING TARGETS **
All 50+ bullets shot for the preceding targets were measured for speed (feet/second) by an Oehler 35 Proof chronograph with printer (picture 1 (1L - 1H)) at about ten feet from the muzzle. The 35P chronograph uses three detectors, instead of two, which allows bullet speed to be measured twice.
On each of the targets is the printout from the 35P chronograph printer. On the first five lines of each printout is the bullet’s Proof Velocity, followed by the Shot Number, and Primary velocity. On target 1 (T1) the first line shows a Proof Velocity of 2824 fps, the bullet number 01, and a Primary Velocity of 2815 fps (2824 - 01 - 2815).
On each of the Oehler printouts below the five bullet number and speed lines are five more lines (‘------’ lines not included). These five lines give the group’s Highest Velocity, Lowest Velocity, Extreme Velocity Spread, Mean or Average Velocity, and Standard Deviation. For target 1 (T1), the Highest Velocity is 2821 fps, the Lowest Velocity is 2801 fps, the Extreme Velocity Spread is 20 fps, the Mean or Average Velocity is 2813 fps, and the Standard Deviation is 7 fps.
** 300 YARD TARGETS 11 - 12 (3rd shooting session) **
The temperature was between 55-65 Fahrenheit, the relative humidity was 47%, and barometric pressure was around 30 inch hg.. A 5 mph head wind with gusts of up to 20 mph was coming from the 1-1:30 o’clock direction, which was very close to an ideal 12 o’clock direction.
I shot from a Protektor mechanical rest with sand bags mounted to wood and placed on top of a car (picture ?). The car was positioned up hill from the 300 yard target; the vertical elevation from the target to the car was probably 60-feet. The hill portion was only 1/3 the distance to the target; the other 2/3 distance consisted of gently sloping land. Because of the land layout and head wind, mirage effect was probably eliminated.
The Nikon scope was at 9X power, and its reticle had not been adjusted since the adjustment made while shooting at the 100 yard target. Because the scope sits relatively high above the barrel, I chose to vertically level it with a bubble level installed on top the scope before each shot. The time between shots was increased to around 2 minutes. To prevent recoil fires and to allow me to concentrate on attaining better trigger pulls from the 6-7 lb. single-stage trigger, I loaded only one bullet into the magazine after each shot.
* 300 YARD TARGET 11 *
300 yard target 11 (T11) was shot with Hornady V-Max 40 gr. Moly-coated plastic-tip ammo The point of aim was the top target’s center red bulls-eye. Although bullet speed wasn’t measured, from previous measurements we know that bullet speed was probably between 3227 and 3278 fps with this rifle. A 2-shot group measured 7/16", the 3-shot group measured 1-1/4", the 4-shot group measured 3-1/2", and the 5-shot group measured 4-3/4". Incredibly, had a rigidly mounted shooting rest, a 2-stage trigger, and a higher power scope been used, I feel the 5-shot group could have measured around 2-1/4 inches.
* 300 YARD TARGET 12 *
300 yard target 12 (T12) was shot with Hornady V-Max 55 gr. Moly-coated plastic-tip ammo The point of aim was the top target’s center red bulls-eye. Although bullet speed wasn’t measured, from previous measurements we know that bullet speed was probably between 2748 and 2830 fps with this rifle. A 2-shot group measured 2-1/8", the 3-shot group measured 3-3/4", the 4-shot group measured 5", and the 5-shot group measured 9-3/8". Incredibly, had a rigidly mounted shooting rest, a 2-stage trigger, and a higher power scope been used, I feel the 5-shot group could have measured around 3-3/4 inches.
**** SHOOTING OBSERVATIONS ****
** GROUP SPREAD **
The 5-shot group spread was mostly attributed to shooting off a shooting rest that wasn’t rigidly mounted (a lightweight gun needs a rigid mount to help keep it still, whereas a heavy rifle is fairly easy to keep still). Not eliminating scope parallax error could have attributed significantly. Where applicable, not allowing a full 1 minute cool down period between shots definitely attributed to an increase in spread. The single stage non-adjustable trigger also played a significant role in increasing the spread. The flash hider may have had a small role in expanding group size.
** INCREASING ACCURACY **
What could be done to decrease group spread size? Well, a rubber "Accu-Wedge" didn’t need to be placed in the receiver area to take out any movement between the upper and lower receivers, as this gun’s receivers had been "matched" very accurately by a machinist. Positioning one’s head to exceed the scope’s eye relief and shrink the image, and then center the image on the glass to help minimize scope parallax error would be very beneficial. Installing a 2-stage adjustable trigger system in the lower receiver would definitely help get rid of the "flyer" in any 5-shot group. Installing a premium barrel that has tighter dimensions, especially in the chamber area, would help accuracy. Installing a free float barrel hand guard would help accuracy. Actually, since the upper receiver quickly attaches/detaches to/from the lower receiver, it would be best to have another upper receiver on hand that has a premium bull barrel, a removable carry handle, a 7/8" dove-tail scope mounting rail under the removable carry handle, a removable front sight, and free-float barrel hand guards. Also, having an upper receiver that has a premium barrel and a twist rate that is optimal for the ammo being shot would be desirable, as bullets less than 40 gr. to over 80 gr. are available. The barrel end’s bevel/crown plays a key roll in bullet accuracy. Removing the flash hider could only help reduce group size. The list goes on and on.
** BULLET OBSERVATIONS **
The Hornady V-Max Moly-coated plastic-tip ammo and Israeli SS-109 ammo were the most accurate ammo, and they were comparably accurate to one another (more tests will be performed to see which ammo is the most accurate at different distances). The South African 55 gr. FMJ ammo was the least accurate. Although a 1:7 barrel rifling twist rate is what is recommended as being optimal for shooting the Israeli SS-109 bullets, the 1:9 twist rate seemed to do a good job in stabilizing the SS-109 bullet out to 225 yards. When shooting the V-Max Moly coated ammo through a clean barrel----the barrel remained incredibly clean!
** B-SQUARE ALUMINUM SCOPE MOUNT **
The B-Square scope mount’s single mount-to-gun attaching nut did need to be tightened fairly often; however, this undesirable loosening was considerable lessened after a fiber washer was placed behind the thumb screw. The B-Square mount’s scope attaching hardware (4 hex screws) didn’t loosen. The mount mated very well with the AR-15 carry handle (no play/movement). Each time the scope and mount assembly was removed and replaced, the point of aim never changed. The AR-15 iron sights are easy to use with the B-Square "see through" scope mount in place.
**NIKON 3-9X50 Buckmasters #6435 rifle scope**
We liked everything about the Nikon 3-9x50 scope except that the reticle lines were too thick, in our opinion. If the reticle lines were thinned at the center cross hair, this scope would be much more accurate.
*************************** AR-15 SPARE PARTS ****************************
** HIGH-LOSS, HIGH-BREAKAGE BOLT & BOLT CARRIER PARTS**
1. EXTRACTOR, EXTRACTOR SPRING, RETAINING PIN
2. BOLT-CAM PIN
3. FIRING PIN AND RETAINING PIN
*************************** GUN REVIEW #3 PICTURES **********************
Pictures associated with this review can presently be viewed on-line at CAR-15 REVIEW PICTURES.
T1 (T1L - T1H): Remington UMC 55 gr. FMJ at 50 yards
T2 (T2L - T2H): Hornady 55 gr. V-Max at 100 yards
T3 (T3L - T3H): Hornady 40 gr. V-Max at 100 yards
T4 (T4L - T4H): Hornady 55 gr. V-Max at 100 yards
T5 (T5L -T5H); Israeli SS-109 63 gr. at 100 yards
T6 (T6L - T6H): SO. AFRICAN 55 gr. FMJ
T7 (T7L - T7H): Hornady 40 gr. V-Max at 225 yards
T8 (T8L - T8H): Hornady 55 gr. V-Max at 225 yards
T9 (T9L - T9H): ISRAELI SS-109 63 gr. FMJ at 225 yards
T10 (T10L - T10H): SO. AFRICAN 55 gr. FMJ at 225 YARDS
T11 (T11L - T11H): Hornady 40 gr. V-Max at 300 yards
T12 (T12L - T12H): Hornady 55 gr. V-Max at 300 yards
T12-CLOSE-UP: Close-up of 300 yard 55 gr. Hornady V-Max 5-shot group
1 (1L - 1H): OEHLER 35P CHRONOGRAPH
2 (2L - 2H): PROTEKTOR SHOOTING REST
3: 1.8 mb SHOOTING VIDEO
4: AMMO (only 4 types were used)
5 (5L -5H) PROTEKTOR SHOOTING REST USED DURING 300 YARD SHOOTING TEST.
COPYRIGHT 2001 EXTREME PRODUCTIONS. ALL RIGHTS RESERVED.
Law that forbid ownership of arms disarm only those who are neither inclined, nor determined to commit crimes. Such laws make things worse for the assaulted and better for the assailants. They serve rather to encourage than to prevent homicides, for an unarmed man may be attacked with greater confidence than an armed man. --Thomas Jefferson