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load for sako trg for 1000 yards


moc1

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hi guys,

 

im going to try the 1000 yard range at bisley next week and wondered if anyone had some advice on some good loads. my guns a sako trg22 in .308 with the 26'' barrel, ive been told the 155 lapua scenars are the best so i brought a couple hundred of these. so loads for the 155 please.

 

my local shop can get N140, RL-15 and IMR 4895, ive also been told for 1000 yards i will need a speed over 2900 fps out of my 26'' barrel, any help appreciated.

 

 

thanks

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N140, book max is 43.7 if I remember correctly. BUT, it seems light, and a lot of people run up to, and higher than 46. I run 46 in a tikka 595 with the same twist, 24" barrel, and it does well at 1000. Usual rules apply, work up to it, especially when running above book loads. Be warned, from experience, TRG's seem to show pressure signs earlier than some others, oakens shows hot at 44gr of Varget

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I ran 155 Scenars over 46.5 of N140, lapua brass and br2 primer loaded out to Max mag length - 2.9" as I recall. It's clearly over book Max so work up. 46.0 of Varget gave me the same velocity but N140 is obviously easier to come by.

 

Tony

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My TRG won't cut the mustard at 1000 yards with any N140 load, with 155 grain Scenars SMKs or Berger's. I say 'any' because I get pressure signs with 45.6 grains and very tight bolt lift with 46 grains. I got near the magic 2900 fps with 46.3 grains of Reloder 15. The best velocity load with Lapua Scenars is with N540 but this won't do your barrel a lot of good over time.

After a lot of recent experimentation my best velocity loads so far come from 47.5 grains of TR 140, using a drop tube to get it all in the case. This is with the Scenar and Palma bullet seated to 2.860 COAL. The other load that shows promise is 47.2 grains of N540 with the Sierra Palma bullet. Strangely, this latter load is OK in my TRG but it gives nasty pressure signs in my AW. Like I say, it gives me good velocity but I want to keep my original TRG barrel (and my shoulder) a bit longer.

 

The old carrot and key advice is to work up carefully. If you know someone with QuickLoad they will be able to give you some good start and safe end-points.

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Be warned, from experience, TRG's seem to show pressure signs earlier than some others, oakens shows hot at 44gr of Varget

I'm still not convinced that the pressure issue with my TRG isn't an interesting (8lb) batch of Varget. I have not been able to obtain more for comparison. It gives higher than expected velocities in my .243 but no excess pressures. Not going to buy s/h powder again.

Was going to experiment with N140 and 155 scenars next, over to you on that one Pete.

 

To the OP, you are going to have to push it hard to get the velocity for 1000yds. Sure your bullet will get there but no where near competitively. I used to find my trg to be excellent at 900 but lacking at 1000, presumably to do with insufficient velocity. That is with scenar and both SMK's.

IMHO, if you want to shoot 1000yds you need the right tool for the job, be that a longer barrel or a more efficient chambering.

Rup

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I'm still not convinced that the pressure issue with my TRG isn't an interesting (8lb) batch of Varget. I have not been able to obtain more for comparison. It gives higher than expected velocities in my .243 but no excess pressures. Not going to buy s/h powder again.

Was going to experiment with N140 and 155 scenars next, over to you on that one Pete.

 

To the OP, you are going to have to push it hard to get the velocity for 1000yds. Sure your bullet will get there but no where near competitively. I used to find my trg to be excellent at 900 but lacking at 1000, presumably to do with insufficient velocity. That is with scenar and both SMK's.

IMHO, if you want to shoot 1000yds you need the right tool for the job, be that a longer barrel or a more efficient chambering.

Rup

+1 on that paragraph. The Sako TRG is very accurate up to 800 yards. After that it struggles against the longer barrelled rifles.

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+2,on Oaken and Brillo's realism for factory 308s at 1000y.

My VSSF would turn in some sub moa groups,on very benign days,but otherwise ,1 to 1.5 moa was more typical.Others were no better.

So when we hear of factory 308s shooting at 1000y,"gets there no problem",It's as well to bear in mind,the bullets won't usually be grouping any better than that.Fine,good fun-but not 'competitive' with more appropriate cartridges/rifles,though challenging enough in it's own way,and a "respect the wind-it usually wins" learning experience!

(If you want to get competitive with the 6.5-284,let alone the hot 7mms,you'll need ballistics like these in a 30 calibre: 220 g BC .627,at 2650 fps. Recoil will be up almost 50% on the 6.5,so you won't be firing 5 shots in 20 secs,and to tame that recoil you'll need about 23lb rifle,so you will be in with the heavy guns....

slightly better news is that your barrel will last longer than the hot shots,though you might want to change before then. No reason not to enjoy,meanwhile,just to be realistic about 308w capabilities,approaching the limits of it's shootable envelope,in non specialised (palma etc) rifles.

Gbal

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thanks for all the advice, i'll buy a tub of n140 and n540 and start the loads about 43 and work up. maybe i'll get lucky with the n540 and get an accurate load thats above the 2900 - 2950 fps range. either way i'll have a lot of fun in the process. once the barrel is burnt out i'll swap for maybe a .260 rem which might help a bit.

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thanks for all the advice, i'll buy a tub of n140 and n540 and start the loads about 43 and work up. maybe i'll get lucky with the n540 and get an accurate load thats above the 2900 - 2950 fps range. either way i'll have a lot of fun in the process. once the barrel is burnt out i'll swap for maybe a .260 rem which might help a bit.

 

OK-wearing out will take a while-even with hot powders-but 260 does have better ballistics.It's all relative-if you are happy with your rifles performance judged by other comparable calibre/rifles, absolutely fine.Some get envious of groups etc half the size,in which case you pay's your money.....but it isn't compulsory-and until you've progressed wind reading skill,holes on target will resist close proximity.

Gbal

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thanks for all the advice, i'll buy a tub of n140 and n540 and start the loads about 43 and work up. maybe i'll get lucky with the n540 and get an accurate load thats above the 2900 - 2950 fps range. either way i'll have a lot of fun in the process. once the barrel is burnt out i'll swap for maybe a .260 rem which might help a bit.

Good plan. I've just bought oakens TRG so will be doing the same, as in, pulling the tube and going '260'

 

Let us know how you get on at 1000, you might find the magic sweet spot ;)

 

Pete

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maybe i'll get lucky with the n540 and get an accurate load thats above the 2900 - 2950 fps range.

I reckon you'll wreck a lot of brass trying!

Fortunately the Trg action is built like a tank. ;-)

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i brought some n540 and have started at 43 and worked up in .3 increments to 45. loaded at 2.85 oal. hopefully get to the range on wednesday to test them out.

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Of the powders you can get, IMR-4895 is likely the best for what you have in mind. It gives amongst the highest MVs going with 155 to 175s in 308, and is usually easy to tune. It outperforms both H4895 and H. VarGet in this regard, and N140 by a large margin.

 

If the TRG has an 11 or 12-inch barrel rifling twist rate, the best bullet to use in this application is the 175gn Berger Tactical OTM, specially designed for the US military's recently adopted 11.25-inch twist rate for 7.62mm sniper and marksmens' rifles. Bryan Litz who designed the bullet had the objective of complete stability through transonic speeds and also while falling below the speed of sound for military ammo that gives 2,600 to 2,650 fps MV from the current generation of big ARs and their 20-inch barrels as well as the longer barrel sniper bolt-action jobs. I imagine that he and Berger hoped to wean the US Department of Defence off the Federal Cartridge Co. manufactured M118LR 7.62 sniper round and its 175gn Sierra MK. if so, it's not happened. (I can't say I'm surprised - there is a lot of shared history and development involving the US Army and ATK / Federal over the M118LR round and the links between the US military and Sierra are very long and very strong.)

 

Litz used to have his own ammunition supply company called Applied Ballitics LLC as well as its being a consulting ballistician, but I believe he's now packed in as it was too much work alongside being Berger's bullet designer. While he was manufacturing ammo (see .........

 

http://www.accurateshooter.com/gear-reviews/applied-ballistics-308-fullbore-ammo/

 

.............. he briefly got around to producing the 175gn 308W and reported that he managed to shoot a one-MOA group at 1,000 yards from a 20-inch barrel semi-auto military style rifle. (Bryan is a top international shooter LR competitor and there is no issue with his shooting and handloading ability. I doubt if he would exaggerate the cartridge's performance either.)

 

There are of course downsides - like it's a Berger which means great bullet but expensive (was around £52 or £53 a box last time I saw them) and probably unavailable at the moment too.

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I followed Laurie's advice from an old Target Shooter article and tried the 190grn Sierra Matchking in my Reminton 700 with a 1 in 12, 26 inch barrel for use at 1000 yards at Bisley. I'm happy to say that these worked very well.

 

Perhaps surprisingly, the NRA's RUAG ammo with the older style 2155 155grn SMK also seemed to perform just as well.

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I followed Laurie's advice from an old Target Shooter article and tried the 190grn Sierra Matchking in my Reminton 700 with a 1 in 12, 26 inch barrel for use at 1000 yards at Bisley. I'm happy to say that these worked very well.

Perhaps surprisingly, the NRA's RUAG ammo with the older style 2155 155grn SMK also seemed to perform just as well.

+1 700 VSSF ten years ago-43.6 V 140 190 SMK (moly) 2558 (65F),2531 (35F).

43.4 V 140 with scenar 185 (m) 2595 (60F) were v acc at shorter range,not quite as good at 1ooo.

 

Of course things have moved on (molygone),but this combination seemed about as good as any standard factory 308 then,at best 1/2 moa,more typically 1-1 1/2 moa.No endless fiddling with powders ,bullets ,seating etc etc,as it was pretty obvious this was an accurate load ( sub 1/2 moa),and what was needed was a lot more skill in wind reading,where there was much more room for improvement ( 1/2 moa rifle hasn't much room to improve,10 inches of wind reading error has!!)Of course,such skill can't be bought,or got by endless 'load development'.I doubt that that truth has changed,though there are now better bullets etc,if you can get them,as Laurie advises.

Gbal

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Perhaps surprisingly, the NRA's RUAG ammo with the older style 2155 155grn SMK also seemed to perform just as well.

 

 

This is all about bullet behaviour in the worst bit of the transonic zone (after reaching ~1,226 fps and dropping down to the speed of sound at ~1,126 fps) and if it applies passing through the sound barrier into subsonic flight.

 

Forget all the conventional stuff about bullet A being 'better' than B because it has a higher BC. It could well be (in fact I'm pretty sure it is the case) that a traditional 7-calibre radius tangent ogive Sierra outperforms a 13-calibre radius secant ogive VLD or Hybrid at these iffy velocities.

 

The problem is there is no easy way of identifying a good performer from a poor one other than experience and what you might read about other people's experiments or experience. If a transonic bullet still hits the target at 1K OK, but suffers say 50% more wind drift in the last 200 yards of flight compared to another design, how do you know this unless you're a very good wind reader and know those range conditions like the back of your hand?

 

The evidence I've seen to date is:

 

The US Army did tests on the old Frankford Arsenal 173gn FMJBT that was the standard US military sniper / match bullet for years covering the end of the .30-06 service era and start of the 7.62mm. It was found that groups dispersion increased by 50 to 100% if retained velocity dropped to within 100 fps of the speed of sound, ie anything below 1,226 fps, wind drift effects were also significantly increased. This and other features led to the US Army commissioning Sierra to produce an improved .30 cal 175gn bullet, giving us the widely used and tolerant 175gn Sierra MK.

 

John Carmichael, now better known as the proprietor of HPS Target Rifles Ltd and manufacturer of HPS TargetMaster ammo, designed and built a traditional two metal-covered screen chronograph 20(?) years back in the days when Walt Berger had just designed his first VLDs, but Target Rifle still used 146gn RG Green Spot, and the original (#2155) 155gn Sierra Palma MK was the most efficient TR / Palma bullet on the planet. The bullets were shot over an optical chronograph at the muzzle and the big screen type was placed at the butts in front of a target on Stickledown. Nobody then prior to the US Army and others allowing the use of ground located Doppler radar installations really knew what bullets' actual realistic BCs were, especially at long-range. This was of particular interest to the Match Rifle shooters using 180-200gn Sierras in 308 Win at up to 1,200 yards. John found that bullets went much slower at 1K than people had believed, also that 150-155gn VLDs fired from a standard 30-inch tight barrel TR rifle at ~2,950 fps MV lost less speed than conventional tangent ogive designs up to 800 yards, but lost it a lot faster between 800 and 1,000 so they were in some cases going slower than conventional designs. The obvious conclusion was that VLD types produce less drag at high supersonic velocities, but more at low supersonic / transonic speeds - whether that applies to today's VLDs, long nose tangent LR BTs, Hybrids, whatever? Who knows - bullet design has moved on a huge amount in 20 years.

 

Certain designs, many of them from Sierra have a reputation for coping well with these adverse conditions, this learned through trial and error. The .30 original 155 SMK (#2155) is one such, the 190 and 200gn SMKs (favourites of the MR shooters for decades after Sierra changed the originally long boatail 180 SMK to its present short BT, short-range design). I know from personal experience that the 0.224 80gn SMK stays completely stable even at subsonic speeds at 1K from my early .223 Rem LR days - VLDs and the 80 A-Max seemed less so at what were inadequate MVs for shooting at this distance.

 

There is apparently a close relationship between bullet shape, speed and rotational speed hence the Litz designed 175gn Tactical OTM that loses its special transonic benefits if fired in a twist rate that is too far off that of the optimum 1-11.25", ie in 1-10 or 1-13 barrels.

 

Finally, there are the military 7mm to 8mm cal FMJBTs designed for concentrated MG use. Back in WW1, MGs went over the four years from being issued at the level of two Vickers per British infantry battalion (a lot more MG08s in their German equivalents), and using the standard rifle round to being used in massed formations by 1918 as rifle calibre artillery firing at high elevations on fixed lines to drench the other side's rear areas, support and communications trenches with hails of subsonic bullets plunging in at steep angles, which although slow would still injure and kill. Early ammo only allowed 3,000-3,500 M extreme range. Use of heavier BT designs added 1,000-1,500M extreme range because of their much increased efficiency in trans and sub sonic speed ranges. These bullets tend to be much shorter than most of today's speciallist target designs. Lapua developed its famous D-series between the wars for 7.62X53R MGs and the 185/200gn D46s are the survivors of this once large genre. The step-boattail .308" D46 185 has gone out of favour for target shooting these days - although US .30-06 shooting guru German Salazar is still a fan - but this is another bullet with an excellent reputation for coping with transonic speeds. The various military bodies who designed the originals may not have had today's computer aids, but they found out what worked partly through theory, mostly through trial and error - and the ballistic facts of life haven't changed in 80 years or so.

 

Finally, we know what doesn't work at transonic speeds - those with a boat-tail angle greater than 10-degrees. That's all .30-calibre 168gn match bullets other than the three Berger designs and 167gn Lapua Scenar, all .30 A-Maxes other than the 208gn model, the .30 180gn Sierra MK.

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As always Laurie's posts are a right riveting and informative read. I read a similar post a few months back in reply to a query about the Sako TRG's apparent difficulty at ranges above 800 yards (at least this is the case with mine) and attempted then to obtain the 175 Berger OTM bullets as the TRG barrel has 1:11 twist. Needless to say I had no luck and tried some development with Berger Long Range Boat Tail bullets, P/N 30420, instead.

 

I successfully achieved good ballistics for 1000 yards with this bullet but was disappointed at the relatively poor accuracy compared to the Lapua Scenar 155's. I am still searching for the optimum powder/load combination that will give me the accuracy I need with the Berger 175 mentioned as I've found using 185 and 190 grain bullets quite painful after completing a full detail. This is a pity because the 190 SMK gave me excellent accuracy and 1000 yard performance, albeit the initial elevation adjustment is rather high compared to a 155 Scenar. It is just that out of a 26" barrel the recoil is somewhat unpleasant. Perhaps some girlie padding is the answer.

 

I was particularly interested in the notes about the 175 SMK as I have been led to believe that this bullet is not particularly popular with F T/R shooters. Going by Laurie's comments it sounds like a good option for those of us with shorter barrelled rifles.

 

Laurie, Picking up on the comment about the Lapua Scenar 167 grn bullet, do I understand that this bullet is capable of good 1000 yard performance as opposed to the 168 SMK? It would be good if this is so as I have developed superb shorter range loads with this bullet.

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Brillo,+1 on the recoil issue-the VSSF rem was not a very pleasant rifle to shoot out of the box,and jumped a bit in the rest,fast 5 shot strings were just not possible..The price of a 308w-to be up there with the better 6.5s (142@2950) the 30 cal needs something like 220g @2650,or pro rata on that,and to cope with the recoil to 6.5 level means 23+ pounds weight-which isn't legal in some competitions.

It's not a cissy/softy recoil issue really,though that can be uncomfortable.For non comp shooting,a good moderator would restore some pleasure.

Gbal

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The 175gn SMK isn't at all popular with LR F/TR shooters - a good design but simply too low a BC by today's standards at 0.243 G7. That's barely higher than the 155.5gn Berger BT and 155gn Hybrid which can both be pushed out a lot faster. Like the 168gn SMK and similar, it can make a superb short range match option if you can come up with a combination that shoots into a single hole at 100 yards.

 

(What many people forget in all the business of comparing bullet / velocity combinations in a 10 mph true 90-deg crosswind, is that one rarely encounters such a change between shots. Assuming one's scope has enough windage adjustment to cope with the conditions, the absolute wind effect is only a concern for getting onto the frame with that first sighter. Alright, I know that's a worry enough for many! However once onto the grid on one's paper target plot - which every TR / F-TR / MR competitor should maintain except in very unusual situations such as barely changing conditions when there is a benefit in rattling shots off to get them into the V fast before a change does happen, it's all about coping with the wind change between successive shots and that's usually nowhere near 10 mph. Having reverse analysed my recorded corrected wind values in MOA on the target using a ballistics program, the equivalent 90-deg wind speed change between any two individual shots rarely achieves never mind exceeds 2mph in matches shot at Diggle, Blair, and Bisley. GB F-Class Assoc round 1 at Diggle a few weeks back saw really horrible wind switches, speed and angle, on the Sunday matches, but although there would be 10 mph actual wind speed changes blowing mostly down the range, they just exceeded 3 mph corrected to a 90-deg crosswind basis - and those were horrible, really exceptional conditions. There may be much bigger variations than 1-2mph 90-deg equiv across the 20 shots in a match of course, but wind tends to build up or die back over time rather than snap into a new very different speed.

 

So, a relatively low BC, but very accurate and cheap design that the barrel likes and really groups tight may be more than good enough for matches up to 600 yards as the absolute difference at that range caused by misreading the 90-deg equivalent wind change by 1 mph is not that great compared to the sooper-dooper best BC on the market model. 1,000 in 308 is a VERY different matter, both in retained velocity and wind effects.)

 

The 167gn and 185gn Scenars are both short-range designs in the 168gn Sierra MK mould, BUT Lapua has kept the BT angle reasonable. While the 155 has a near optimal 7.2-deg angle, the two heavier models are 9.6-deg and 10-deg compared to the 168 SMK and clones at 13-deg. The 175gn SMK is also 9-deg, a bit steeper than optimal but not transonic zone instability inducing.

 

A key indicator of bullet efficiency is the i7 or 'form factor' value which is a drag-based numeric measure of how the subject bullet compares in aerodynamc efficiency to the reference (G1, G7, or G-whatever) projectile. The reference projectile is always given the value 1.000 and the subject being compared is given a lower number if more aerodynamic, 1.000 if identical, and higher if it generates more drag. A subject with an i7 value of 1.1 generates 10% more drag on average than the reference design, 10% less if it's rated at 0.9. The BC is calculated by dividing the SD (sectional density) which is entirely calibre to weight determined by the i7 value.

 

The lighter / shorter a bullet is in relation to the calibre, the more difficult to get a really low i7 number, so 150 and 155gn .30s are up against it, and will never match a 140gn 6.5 or 180gn 7mm.

 

Even so, the best 155 .30 around until recently was the 155 Scenar and its i7 value is 0.988 - a lot better than the first Berger high effiiciency 155gn bullet the VLD at 1.039. The original Palma MK (2155) is 1.092, over 10% less efficient than the Scenar. However, we now have the Berger 155.5 BT also at 0.988and 155 Hybrid at 0.945, a figure that ballisticians would likely say was unachievable not so many years ago.

 

The 175gn SMK is a relatively poor 1.085, the 168 SMK worse at 1.161. The 190 and 200 are 1.070 and 1.058 - low by today's standards, but their saving grace is their well known tolerance of low speed flight. The much more recent 210 SMK is in a different league at 1.000 excactly.

 

Returning to the heavier Scenars, the 167 is 1.163, a very high drag design by modern standards (the superb 168gn berger Hybrid is 0.953 by comparison), and the 185 is 1.130. However, these high drag designs often seem to give good short-distance performance - so you pays your money and makes your choice. Incidentally, Lapua seems to have stuck to this approach with the new 175 and 220gn Scenar-Ls, both of which are relatively high drag models, not making any attempt to challenge Berger for low i7 / high BC designs for the LR 308 win shooter. The 220 has a very long middle bearing section that will also add to in-barrel friction and coppering. Strange! Maybe it's designed for military sniper use in .300 Win Mag?

 

Re the recoil issue with heavies especially in a factory weight rifle, I sympathise. Years back Sth Yorks Shooting Supplies sold the PAST 'Recoil Shield' a thin high-friction material coated recoil absorbing pad available in various grades. I used the 'Magnum' model when I shot a relatively light .300 H&H Mag in the early days of F-Class from a lightish rifle. They really do make a difference - not cheap but effective. I don't know if Roger at SYSS still does them - a quick Google suggests Edgar Bros is the distributor now so we're probably scr**ed. (Incidentally, it gave me a great respect for the female of the species' getting into and out of a bra each day - people used to congregate and watch me try to get my PAST shield on in the Strensall car park before setting off for the firing point!)

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Great info Laurie. i7 seems to help explain quite a bit that BC alone doesn't ....interactional effects can get real tricky!

 

There was a female version of the Past,which might have diverted some of the unwanted car park attention ....as I recall ... from a past female shooter...

 

Pete-yes,an investment....did your 444 have the vicious twin jabber ends to the steel lined butt 'pad',as on the big lever action Brownings etc? No fun at all.

Gbal

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Great info Laurie. i7 seems to help explain quite a bit that BC alone doesn't ....interactional effects can get real tricky!

 

There was a female version of the Past,which might have diverted some of the unwanted car park attention ....as I recall ... from a past female shooter...

 

Pete-yes,an investment....did your 444 have the vicious twin jabber ends to the steel lined butt 'pad',as on the big lever action Brownings etc? No fun at all.

Gbal

No, but the standard butt plate was made of Bakelite by the feel of it, and as I run it at full house to flatten the trajectory as much as poss, coupled with a missing inch of collarbone, I needed to do something, it now wears a pachmyer pad, and I can handle about 30-40 shots off a bench before the shoulder crunches too much. But 50 shots still causes enough internal grief to literally deaden my arm for a few days without using the past pad, with it I could shoot all day.

 

Pete

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Laurie, many thanks for the really interesting and comprehensive reply. It seems like I was fortunate in picking two bullets that would work quite well in my rifle at long range. The other good thing about the Sierra 155grn (#2155) and 190grn SMKs is that they are readily available; unlike many of the modern, efficient Bergers! They are also available in reasonably priced ammo from the NRA and HPS.

 

I didn't find the recoil too bad with the 190grn bullets. My solution is an AICS - nice and heavy! I also have a moderator on order, which should make it even easier.

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