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> Opinions Wanted: 3 cluster 6 shot group
Opinions Wanted: 3 cluster 6 shot group
@ 06:41 pm (GMT) |
deerndingoHi All,Well I finally took out my brand new 700SPS in 7mm RM. I loaded up a tryout load of some Winchester brass (couldn't get Nosler), 162gr SSTs, and a light load of 64.5gr of AR2213SC. After initial sight in I then shot a 6 shot group. Each shot was shot at least 10minutes apart. The first Location 1) landed 1.5" High and 1.5" to the right. The second landed .25" high and .25" to the right location 2). The third landed .75" high and .25" to teh left (location 3). The forth touched location 2. The fifth touched location three. At this point I pulled my glasses off, refocused teh optics and the sixth touched location 1. The stock had been bedded, but only around the screws and recoil lug. I'm thinking "cheap plastic stock". What are you thinking? |
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@ 09:17 am (GMT) |
Nathan FosterRe: Opinions Wanted: 3 cluster 6 shot groupOK, here is what should have been done prior to test shooting:Stabilize the forend with epoxy resin (see our stabilizer product) Bed the action and first 1" of the barrel. If the first 1" of the barrel; is not bedded and the barrel has been free floated, chances are it won't shoot as the stock is flexing up and pinching the front of the recoil lug to varying degrees. It is the recoil lug inlet of the SPS stock that is the weakest point. Failure to reinforce this area during bedding- then free floating the barrel will often destroy accuracy. Check the mag box is not pinched on re-assembly, the mag box shgould have some slop in it. Adjust trigger to 1.5lb. More than likely, your X-Pro trigger wont go below 4lb and needs to be replaced with a Timney. Only very experienced shooters can shoot extremely tight groups with a 4lb trigger weight. Break the bore in. The groups you have described are less important than a study of the bore at the muzzle, study the fouling. If the fouling is heavy or very stubborn, the bore needs further lapping work. The traditional method of fire a shot and then clean with solvents won't work on your bore. Please see the barrel break in article on the site. Do not use a bipod for range work. Use sand bags, use a sling, use good forend control. See the 'hold that forend article'. The SPS is a light weight rifle producing considerable recoil (relative to accuracy potential). You must learn to control this recoil if accuracy and a constant POI is to be maintained. It is not uncommon for seasoned hunters to struggle to shoot the SPS Magnums, groups of around 1.5" at 100 yards are normal. Shooting skills have to be taken to a new level to break this barrier. Start your test loads at 68 grains. 64 grains will be yielding about 2700fps, bulk density will be poor. If you have lengthened the throat as you planned to do, 64 grains will be yielding about 2600fps. If any of the above is neglected, do not expect good results at the range. The groups you have described are 2 MOA (2"), not 10 MOA. Have a work through the above issues, it is going to take time and patience. |
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@ 06:58 pm (GMT) |
deerndingoRe: Opinions Wanted: 3 cluster 6 shot groupNathan,I fully agree with what you've said. I took it to the smith for bedding and strengthening. He bedded it...only around the recoil lug and rear screw. He wouldn't do the rest of it??? I've touched base with another one and he wants more to bed it than it wouild cost for a B&C Medalist. So now I'm thinking after market stock. |
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@ 10:11 am (GMT) |
Nathan FosterRe: Opinions Wanted: 3 cluster 6 shot groupAn aftermarket stock is never a bad thing. Just bare in mind that you will still need to bed the aftermarket stock for optimum accuracy.To work out whether a bedding job / smith is expensive: A proper bedding job should take 12 hours from start to finish. If you have a look at how much local tradesmen cost in other fields (say a mechanic), you'll have an idea. Mechanics here cost $60 per hour. 12 x $60 is $720. I charge $360 for a bedding job and another $240 to complete the project with load development (plus the cost of consumables). It takes $35 to 40 hours to complete a full accurizing job. In other words, for a weeks labor, I get $600- providing the weather plays ball and allows me to complete the test shooting within that week. |
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@ 06:41 pm (GMT) |
deerndingoRe: Opinions Wanted: 3 cluster 6 shot groupNathan,I would love to let you loose on my rifle, but the export and import of rifles from Australia is fraut with paperwork, government regs, poor handling in post and little hitlers. |
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@ 02:08 am (GMT) |
Crap gameRe: Opinions Wanted: 3 cluster 6 shot groupIn addition to the very informative info provided so far, I have never been able to get SST's to shoot accurately in any of my rifles.Not sure if others have experienced this either? The Amax on the other hand seems intrinsically accurate and easy to dial in. |
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@ 05:33 pm (GMT) |
Nathan FosterRe: Opinions Wanted: 3 cluster 6 shot groupThe SST can certainly be more finicky. The reason the A-Max is easier to work with is that its soft/thin jacket swages more easily to the bore. The traditional Interlock is also soft and easy to work with in this regard.Harder bullets like the SST and Scirroco tend to be more sensitive. I can only offer one theory, that the harder nature of these bullets create different and more pronounced harmonic vibrations. The evidence for this can be found in experimenting with seating depths. To get the SST shooting, it can at times involve experimenting with 3 different seating depths, working up through the full range of incremental powder charges. Sometimes I strike it lucky and basic hand loads will get the job done, other times I have to experiment with seating depths. Of late, I have been seating SST bullets .2mm /10 thou of the lands of client rifles. This seems to work well- but it is not always the case. Sometimes I have to go completely the other way, a very big jump, altering the timing of the harmonic vibrations. |
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@ 05:19 am (GMT) |
Crap gameRe: Opinions Wanted: 3 cluster 6 shot groupNathanThank you for the information. I have always wondered what the difference might be as essentially they look the same apart from the canelure on the SST ofcourse. Makes total sense. |
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