Savage 6BR build and performance at local 300 yd benchrest matches

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John_177

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Hi All,

I’ve enjoyed reading lots of great posts in this forum and have finally decided to post something for the first time. It’s a pretty long story of how my new Savage target rifle did at my gun club’s (Niagara Sportsmen’s Association) 300 yard benchrest matches. I've always been interested in seeing more detailed reports on how target rifles perform, not just a few cherry-picked groups, so I'm sharing all my targets for the four matches in which I participated. I hope that you find the story interesting and would greatly appreciate your help on some questions that I list at the end of the post.

At 300 yards it was nearly impossible to see the bullet holes in the black bulls (it helped if the bullet cut a ring), so you couldn't really make scope adjustments during the match. We shot 10 shots each into two bulls (one bull per relay, so you could make a scope adjustment after the first 10 shots). We used 300 yd F-Class (MR-63F) targets.

This was only my second year competing in local benchrest matches, so I still have a lot to learn. In the first year I used a Model 1896 Swedish Mauser in 6.5x55 with a Douglas barrel (DIY installed) and a homemade stock. I got third place, which isn’t bad for an action that was made in 1923, but that’s a whole other story. In the second year, which I’m reporting here, I used a Savage 12, which is actually the only powder burner in my safe that was made in this century!

Figure 1 shows profiles of the rifle. It’s a Savage 12 Target Action with a Criterion 26” barrel in 6BR Norma with a 1 in 8” twist. The stock is homemade from a Richards Microfit laminated blank. The scope is a Sightron SIII 10-50x60 Field Target on Warne QD mounts. I use this scope on two centerfire rifles, a spring piston air rifle and a Kimber 82G rimfire rifle, so I get a lot of bang for the buck from this scope. I think it's a lot better to have one really good scope that is swapped onto four rifles than four mediocre scopes that are dedicated to these rifles. POI changes less than 0.5 MOA when switched from one rifle to the next.

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Figure 2 shows the accessory rail (Rockler Universal T-Track) that I inletted into the bottom of the forend. The 3” wide wooden support block was made to better fit the wide owl ear sandbag on the front rest.

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Figure 3 shows the DIY aluminum bedding block that was glued into the stock. The receiver was then skim-coat bedded into the aluminum block with Acraglas Gel and the barrel and receiver tang were free-floated. I like the fact that three screws (all in front of the trigger) hold the receiver into the bedding block.

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Figure 4 shows the stock adjustment hardware that I made to allow the cheekpiece and buttpad to be moved.

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Figure 5 shows the two bulls from my first match. The 10 ring has a diameter is 2.85” and all but one shot were 10s. The 9 was on the second (right) bull at around 11 o’clock. It didn’t miss by much and I probably would have gotten a 10 if I were shooting a 6.5mm instead of 6mm bullet! I should have adjusted my scope down and right after the first bull, but was worried about the scope not settling in for the second bull. After this I always made adjustments after the first bull. I was lucky to keep a shot inside the 10 ring at 12 o’clock on the first bull, when my neighbor fired his 30-06 just a moment before I pulled the trigger and my POA jumped up. Still, I was happy with my 199-13x score, which was a personal best.

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Figure 6 shows the targets from my second match. I switched to IMR 4064 by accident (it was all that my local gun shop had in stock and I had read that it should work with 6BR). 27.0 grains of IMR 4064 powder produced slightly lower muzzle velocities around 2620 fps compared to 2700 fps for the same charge of H4895, but tightened groups up quite a bit. I wish that I had discovered this powder before the first match! These are pretty mild loads, but I found that accuracy was better with the 107 grain Sierra Matchkings going around 2700 fps or less. After months of searching, I was able to find some Varget, which allowed me to push the muzzle velocity to 2820 fps, but accuracy was not as good. I’ve read that more muzzle velocity is better in benchrest shooting, but in N.G. Papagalos (pp. 53-56, Precision Shooting, March 2005) also found the best accuracy for 107 grain Sierra Matchkings in the 2600-2700 fps range with the 6BR (and he was trying to increase MV to knock over a 50 pound ram silhouette at 500 meters). Has anyone else seen this in their 6BR rifles?

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Figure 7 shows the targets from my third match. I reduced the powder charge of IMR 4064 to 26.8 grains. I was a bit lucky to keep a shot at 3 o’clock in the 10-ring on the second bull! I had one wind flag and didn’t notice any wind change for this shot, so I’m not sure what caused this.

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Figure 8 shows the targets from my fourth and final match. I included the sighters in the top left corner to show a surprising result. The group in my second sighter target was a little to the right, so I clicked the scope 1 click (1/8 MOA) to the left. It looks like the group on the first bull moved a lot more than 3/8” to the left after that adjustment! This is why I’m a bit paranoid about making scope adjustments during a match. After the first bull, I clicked to the right and got a better centered group on the second bull. The group sizes look pretty good, each with a 10-shot center-to-center distance of around 1.4”. If they were better centered, I would have gotten a lot more Xs!

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I’m very happy with the second place season finish (I tied for first in average score but lost on average X-count). The first place finisher also shot a Savage 12 Target Action with a Sightron 10-50x60 scope, but used a Shilen select match barrel in 6.5mm Creedmoor. I’ve read a lot of complaints about Savage rifles, but the some of the biggest complaints don’t apply for this particular situation. Since I’m using a single shot action, there were no failure to feed or magazine issues. I even removed the ejector to help protect the spent brass, so ejection also wasn’t any issue. Since I’m firing slowly, I wasn’t bothered too much if the sear accidentally tripped and got hung up on the AccuRelease safety lever. This never happened during a match, but happened rarely if I didn’t pull the trigger straight back. If I remember correctly, this happened only a few of times when I was first getting used to the trigger in January 2021 and was wearing gloves due to the cold weather. I really appreciated having a trigger pull of around 6 ounces, which allowed me to fire the rifle under free recoil with almost no body contact with the rifle. This is a great trigger for a factory action, as long as you can shoot slowly! Now if I was shooting in a PRS Match, these are important issues, but for this kind of benchrest match, the Savage worked really well.


I’m wondering if/how I can improve things. If you get the chance, please take a look at the following items and let me know what sort of changes make the most sense:

1. Cases: I’m using Lapua cases. Should I weigh them? Does it help to neck-turn them? I don’t have a tight match chamber that requires neck-turning, but have read neck turning could help with accuracy and reduce muzzle velocity spread. I’m neck-sizing and bumping the shoulders back about 0.002” with a Redding type S bushing die.

2. Bullets: Should I be using flat base bullets for this relatively short range, since they stabilize faster than boattails? I’ve only tried boattails (~100 gr Sierra, Berger, Barnes and Hornady) so far. I also had trouble getting Berger 105 gr hybrids to work as well as the 107 gr MKs. At some point I’d like to try shooting at 600 and maybe even 1000 yards, where boattails are best, but maybe a different bullet and load would be better for 300 yards?

3. New barrel: I have around 1200 rounds through this barrel, so eventually I’ll need to replace it. I’m thinking of getting a Shilen select match, but am bit overwhelmed by all the options: a) 1-7 Special for VLD bullets over 100 gr; b) 1-7.5 Ratchet rifled 4 groove; c) 1-8 Special for VLD bullets over 100 gr; d) 1-8 Ratchet rifled 4 groove. It looks like all of these can be made with tight necks (.272", 0 Freebore) that may require neck turning the brass. Please let me know what barrel you would recommend.

Thanks in advance for reading this post and helping with my questions!

I’ve seen much more impressive groups online, but I hope that you found the story and the results interesting!
 
1. Cases: I’m using Lapua cases. Should I weigh them? Does it help to neck-turn them? I don’t have a tight match chamber that requires neck-turning, but have read neck turning could help with accuracy and reduce muzzle velocity spread. I’m neck-sizing and bumping the shoulders back about 0.002” with a Redding type S bushing die.

Weight sorting is a fool’s errand. If you want to sort cases (not typically worth pursuing), then CAPACITY sorting by water fill is the only sensible method.

Neck turning to consistent thickness, even without a tight neck chamber, can help with velocity consistency, but typically, neck thickness is pretty uniform already in Lapua brass.

What is your current standard deviation on your match load?

2. Bullets: Should I be using flat base bullets for this relatively short range, since they stabilize faster than boattails? I’ve only tried boattails (~100 gr Sierra, Berger, Barnes and Hornady) so far. I also had trouble getting Berger 105 gr hybrids to work as well as the 107 gr MKs. At some point I’d like to try shooting at 600 and maybe even 1000 yards, where boattails are best, but maybe a different bullet and load would be better for 300 yards?

For short range, the flat base target bullets tend to rule the roost. I’ve struggled considerably with 107 SMK’s as well - EXTREMELY jump sensitive - albeit in a different application. I shoot 105 Hybrids like there’s no tomorrow, but I’m reaching long ranges and need the BC.

Are you jamming bullets?

3. New barrel: I have around 1200 rounds through this barrel, so eventually I’ll need to replace it. I’m thinking of getting a Shilen select match, but am bit overwhelmed by all the options: a) 1-7 Special for VLD bullets over 100 gr; b) 1-7.5 Ratchet rifled 4 groove; c) 1-8 Special for VLD bullets over 100 gr; d) 1-8 Ratchet rifled 4 groove. It looks like all of these can be made with tight necks (.272", 0 Freebore) that may require neck turning the brass. Please let me know what barrel you would recommend.

1200 is probably 1/2-1/3 of your barrel life for 6BR. So still quite a bit of viable life left. But do think about about your match and season schedule to be sure you don’t end up at the very end of your barrel life when you need the highest performance.

I can’t speak to what is most popular and best performing for F-class, especially short range, but I use 7” and 7.5” twist barrels, 4 groove and 5R. Twist rate won’t be as critical for shorter, flat based bullets, but you’ll need to make realistic decisions about moving into 600/1,000 class.

I enjoy Bartlein and Proof barrels primarily these days. But Shilen, Brux, Broughton, Benchmark, Krieger, Lilja… hard to go wrong on this list.
 
Since our range only has 300 yards max, they also shoot some reduced target F Class matches at 300. I did it a couple of times, it was fun.

Nice rifle and nice shooting, nothing beats shooting in competition.
 
Weight sorting is a fool’s errand. If you want to sort cases (not typically worth pursuing), then CAPACITY sorting by water fill is the only sensible method.

Neck turning to consistent thickness, even without a tight neck chamber, can help with velocity consistency, but typically, neck thickness is pretty uniform already in Lapua brass.

What is your current standard deviation on your match load?



For short range, the flat base target bullets tend to rule the roost. I’ve struggled considerably with 107 SMK’s as well - EXTREMELY jump sensitive - albeit in a different application. I shoot 105 Hybrids like there’s no tomorrow, but I’m reaching long ranges and need the BC.

Are you jamming bullets?



1200 is probably 1/2-1/3 of your barrel life for 6BR. So still quite a bit of viable life left. But do think about about your match and season schedule to be sure you don’t end up at the very end of your barrel life when you need the highest performance.

I can’t speak to what is most popular and best performing for F-class, especially short range, but I use 7” and 7.5” twist barrels, 4 groove and 5R. Twist rate won’t be as critical for shorter, flat based bullets, but you’ll need to make realistic decisions about moving into 600/1,000 class.

I enjoy Bartlein and Proof barrels primarily these days. But Shilen, Brux, Broughton, Benchmark, Krieger, Lilja… hard to go wrong on this list.

***

Thanks for the insightful and helpful reply! I'm glad that you mentioned standard deviation and bullet seating since those are areas I'm still trying to figure out. Muzzle velocity standard deviation is about 7 fps and extreme spread is around 17 fps for five shots, which I know is not very good and would cause lots of vertical stringing at longer distances. However, at 300 yards, I find that some of my best 5-shot groups have big SDs and some big groups have very small SDs! It seems to me that there's been no connection between low SDs and accuracy in my rifle at 300 yards, if anything, the loads that group best tends to have bigger SDs! Maybe the place where the combustion is most consistent happens to be different from where the barrel harmonics are best?

I've never tried jamming the bullets into the rifling. I tried having the bullets just touch the rifling, which resulted in poor accuracy at 300 yards and much bigger SDs. The best accuracy was around 0.015" to 0.020" off the lands. Would it still be worth trying to go the other way and jam the bullets into the rifling? If so, please let me know how much.

Please let me know what flatbase bullets you recommend. It seems that most of the 6mm FB bullets are a lot lighter, so I'm concerned that they may be too short for the longer throat in the 6BR Norma. For example, would I be able to seat 68gr FB Bergers far enough out to reach the lands? Would this bullet be overstabilized with the 1 in 8" twist.

I'm sorry to be answering all your excellent questions with even more questions. I really appreciate your patience and help!

Best wishes,
John
 
Since our range only has 300 yards max, they also shoot some reduced target F Class matches at 300. I did it a couple of times, it was fun.

Nice rifle and nice shooting, nothing beats shooting in competition.

***
I'm so glad that my club has lots of competitions. That's the main reason I picked it over other clubs when a joined a few years ago. I've made great friends and learned a lot. We also do a 100 yard rimfire benchrest match series. For a report on that, please see:

https://www.rimfirecentral.com/forums/showthread.php?t=1237485
 
Muzzle velocity standard deviation is about 7 fps and extreme spread is around 17 fps for five shots, which I know is not very good and would cause lots of vertical stringing at longer distances.

7SD and 17ES suggests to me there’s a bigger gap than 5 shots are exposing. Any time ES isn’t somewhere between 4-6x the SD, then we know there’s a breakdown in statistical validity. Just a rule of thumb for Normal/Gaussian distribution. 99.7% of samples will fall within +/-3SD, so if we approximate actual Range with sample Spread, then we see ES should be 6x SD. So 7/17 doesn’t quite align with the statistical expectation - we need more shots. More will likely shrink your SD and grow your ES, or maybe grow both.

17fps in my Dasher means a maximum of 5” additional vertical at 1,000yrds, which likely really only means ~2.25” additional elevation within a group… certainly enough to make a difference on scoresheets, of course, but in most perspectives, a very, very small error. Your velocity spread is within the target range I use for my PRS match loads.

However, at 300 yards, I find that some of my best 5-shot groups have big SDs and some big groups have very small SDs! It seems to me that there's been no connection between low SDs and accuracy in my rifle at 300 yards, if anything, the loads that group best tends to have bigger SDs! Maybe the place where the combustion is most consistent happens to be different from where the barrel harmonics are best?

Short range BR is a unique bird. Which is largely why I don’t partake. The 30,000ft view answer is that at short range, mechanical errors grossly overwhelm velocity deviation errors. At 300, in my Dasher, 17fps ES means under an inch of maximum POI influence, and in reality, under a half inch… so for most applications, the influence of velocity spread is moot.

Granted, I tend to find the long range load development methods I use also do yield my best - repeatable - short range groups, with the least flyers, but I fully acknowledge short range load development is as much voodoo as it is science, and statistical analysis of transitional ballistics as indicators of internal ballistics aren’t perfectly correlated with short range performance.

I've never tried jamming the bullets into the rifling. I tried having the bullets just touch the rifling, which resulted in poor accuracy at 300 yards and much bigger SDs. The best accuracy was around 0.015" to 0.020" off the lands. Would it still be worth trying to go the other way and jam the bullets into the rifling? If so, please let me know how much.

@Walkalong can give far better advice to this than can I. I’ve typically found jamming to offer the greatest potential precision when using secant ogive bullets, and when jamming, heavier jam in the 20+ thou ballpark promotes better consistency than 0-5, or 0-10thou. Basically, if you’re going to jam, jam a bunch, don’t just kiss. But yes, certainly fantastic accuracy can be found with jumps, even as long as 150 thou. Walkalong and @Nature Boy can certainly speak to the current trend of jamming in BR and F-class competition.
 
A bullets relative position to the lands is a reference point for seating depth. Since that distance is changing as the throat erodes I would generally “chase the lands” and adjust seating depth accordingly.

My thinking on this has been evolving however and I’m at the point now where I believe that the distance from or into the lands is less important than the bullets position in the case neck.

In other words, I find the best seating depth in initial load testing then stick with it. If accuracy starts to slip and I rule everything else out then I might revisit seating dept. So far, I haven’t chased the lands in ~600 rounds (6BRA) and it’s still laser accurate
 
7SD and 17ES suggests to me there’s a bigger gap than 5 shots are exposing. Any time ES isn’t somewhere between 4-6x the SD, then we know there’s a breakdown in statistical validity. Just a rule of thumb for Normal/Gaussian distribution. 99.7% of samples will fall within +/-3SD, so if we approximate actual Range with sample Spread, then we see ES should be 6x SD. So 7/17 doesn’t quite align with the statistical expectation - we need more shots. More will likely shrink your SD and grow your ES, or maybe grow both.

17fps in my Dasher means a maximum of 5” additional vertical at 1,000yrds, which likely really only means ~2.25” additional elevation within a group… certainly enough to make a difference on scoresheets, of course, but in most perspectives, a very, very small error. Your velocity spread is within the target range I use for my PRS match loads.



Short range BR is a unique bird. Which is largely why I don’t partake. The 30,000ft view answer is that at short range, mechanical errors grossly overwhelm velocity deviation errors. At 300, in my Dasher, 17fps ES means under an inch of maximum POI influence, and in reality, under a half inch… so for most applications, the influence of velocity spread is moot.

Granted, I tend to find the long range load development methods I use also do yield my best - repeatable - short range groups, with the least flyers, but I fully acknowledge short range load development is as much voodoo as it is science, and statistical analysis of transitional ballistics as indicators of internal ballistics aren’t perfectly correlated with short range performance.



@Walkalong can give far better advice to this than can I. I’ve typically found jamming to offer the greatest potential precision when using secant ogive bullets, and when jamming, heavier jam in the 20+ thou ballpark promotes better consistency than 0-5, or 0-10thou. Basically, if you’re going to jam, jam a bunch, don’t just kiss. But yes, certainly fantastic accuracy can be found with jumps, even as long as 150 thou. Walkalong and @Nature Boy can certainly speak to the current trend of jamming in BR and F-class competition.


Good point about the relationship between SD and ES! I'm impressed with your knowledge of Gaussian statistics! Yes, there's just not enough data points to have much confidence in the SD and ES that I gave. It's why I never trust a single 5-shot group to prove how accurate a rifle is (please check out my simulations at: https://www.ctcustomairguns.com/hec...le-dynamics-in-3-spring-piston-airguns-chap-3)! I found a few 10-shot groups where the SD and ES made more sense, but most of my velocity measurements where done when I was changing powder weight or bullet seating depth in bins of 5 shots. I looked at some MV data from my air rifles where I had many more shots, and sure enough ES was more like 4 to 5 times the SD. Getting a factor of six could be pretty rare since points that are 3 sigma away from the average are very rare.

The next thing I'll do is try jamming 0.020". I'm very excited about trying this and will let you know how it goes. We have some snow issues here, but hopefully I'll be able to try this soon.

Thanks again for sharing your time and wisdom!
 
Getting a factor of six could be pretty rare since points that are 3 sigma away from the average are very rare.

Certainly. The general 4-6x span ensures when we have say, 9 tight shots and 1 extreme outlier, our SD can be small, but the range huge - so we know something is very likely broken if we see an ES > 6xSD. Maybe it should be 5x, idk… but we CAN see +/-4-5SD samples within a population Range.

But again, the influence for velocity at short range is exceptionally small compared to mechanical and wind estimate errors. Long range is a different game, so the toolkit is different. I haven’t met many pure short range guys who gave a damn about velocity - and have seen some phenomenal groups which had loads yielding 50fps ES, or even more.
 
For 300 yard Benchrest shooting that the OP is doing, I would probably stay with Varget under those 107 smk bullets but get the speed up there a bit closer to 2850 ish and tune at the distance youre competing at where ever possible.
Ive shot that combination and when you get the tune right you’ll shoot inside those targets assuming your reading conditions well.
 
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He's shooting reduced size target 300 yard F-Class, targets for score, a big difference between it and true registered short range Benchrest.
Regardless of target size my post is still valid, I’ve shot that combination from 100 to 600 yards with Varget and 107 sierras and until I got my speed up and in tune my groups looked very similar to the OPs. My question towards the 7 second delay is related to conditions changing during a slow fire string where if not restricted the shooter could speed up and perhaps tighten up the groups. Either way there is a benefit to being in tune versus trying posted load data from the internet or where ever until we stumble across a load that shoots decent one day then goes away for some unknown reason.

1- case sorting ? If your confident in your scale and charges weight use that chronograph to identify the unexplained odd ball flyers by huge fps swings setting those cases aside to test again, culling the unexplained .
2- for bullets .. I have shot my smallest groups with 107s jumped .016 and never jammed a tangent ogive once. You have to test for yourself to be sure what your rifle prefers.
3-Barrels- mines at 2000 rounds and still shooting 2in groups at 500 yards pretty easily.
 
@John_177
Great shooting indeed
Are you shooting prone or off the bench ? Is there a seven second delay between shots ?

Off the bench. The only rule is that the front and rear rest can't be attached to each other. It's basically F class but without having to get down and up from the ground, which is not so easy for some of us! We have 12 minutes to shoot 10 shots (no sighters allowed during record target). I have one wind flag at 200 yards (maybe it should be closer and I should use more flags?) and try to shoot under the same, prevailing wind condition. I can't shoot too fast since it's a single loader.

This year we'll be using the IBS 300 Hunter Target, so we'll actually be able to see where our bullets land but we'll have less time. This will be more challenging since we're putting two shots into each of the 5 bulls, so there will be a lot of front rest adjusting.
 
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Hi All,

After close to 1600 rounds, the 26" Criterion barrel is still going strong, but the throat fire cracking is getting worse and with barrel delivery times on the order of months or longer, I'm thinking about ordering a replacement barrel. I just want to be ready with the replacement barrel when this one goes.

Please let me know what you think about the following options and questions:

1. Savage Shilen Select Match: these are similar in price to Criterion, but now there are even more options to complicate things!

a) 1-8" Special for VLD bullets over 100 gr.

b) 1-8" Ratchet rifled 4 groove


2. Krieger? These cost about 50% ($200) more than Criterion and Shilen barrels. Maybe the cut rifling is better stress relieved to make the POI less sensitive to barrel temperature?


3. Is there any accuracy advantage to shouldered barrels for the Savage Target Action? This might be an option with Krieger, but it probably would add to the cost.


Most of my shooting will be 300 yard F-class, but someday I'd like to try longer ranges some day, so I'm mostly looking at shooting heavier boat-tail bullets (over 100 gr) in a 1-8" twist barrel. My understanding is that although boat-tails have a bigger BC than flat-base bullets, boat-tails take a longer distance to stabilize and therefore may be more susceptible to wind (lower BC until they stabilize?) at shorter ranges than flat-base bullets, which stabilize very quickly. It's hard to find 6mm flat-based bullets over 100 gr, so it sounds like lighter flat-base bullets with slower twist barrels may be better for 300 yards and closer? I'm pretty confused by all this?!

I think Criterion barrels are great, but part of the fun of this hobby is trying new things and learning new lessons (hopefully good ones!), so I'm leaning towards trying something different.

I appreciate your patience and help. I'm not always a big fan of "tell me what to buy" posts, but hope that the discussion will be interesting and informative for readers besides myself.

Thanks for your help!

John

PS I put a Rifle Basix SAV-2 trigger on the rifle and am glad I did. It's great!
 
I would stick with a Criterion 1-8 twist with their .093 free bore that will allow you to shoot the 103 -105 class bthp. The cut rifling and shouldered barrel or lack there of will NOT hold you back from shooting well.
I promise..
 
This year we'll be using the IBS 300 Hunter Target, so we'll actually be able to see where our bullets land but we'll have less time. This will be more challenging since we're putting two shots into each of the 5 bulls, so there will be a lot of front rest adjusting.

The informal local winter league I joined uses the IBS Hunter targets the first 3 week. Week1 100yds. week 2 200yds. and week 3 300yads. Then we switch off distances and each week is a different target.
 
I would stick with a Criterion 1-8 twist with their .093 free bore that will allow you to shoot the 103 -105 class bthp. The cut rifling and shouldered barrel or lack there of will NOT hold you back from shooting well.
I promise..

Thanks for the helpful advice.
 
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