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Posted: 11/2/2025 10:10:39 AM EDT
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I’ve been thinking about reloading for two AR10s - S&W M&P 10 and PSA PA10. I’ve got a load developed for my bolt gun (175 gr SMK w/ 44.0 gr Varget) which I’d like to use for the sake of simplicity. I’ve tried a few rounds of this load and get about 1.5 MOA with no signs of over pressure in the ARs. However, from the reading I’ve been doing, I see some people saying each AR should have its own load developed. Some articles advise lowering the powder charge from bolt gun levels. Anyone got some real world experience that can share? Thanks |
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Originally Posted By heat762: 1.5 moa for those guns ain't bad Be happy it runs reliably If your chasing smaller groups of course every barrel is different What he said,I did a good bit of work early on in my AR10 load development but ultimately went back to my Remington Mod 7 hunting loads.The only rifle I was able to get to less than MOA was the Sig ,both my DPMS G2 rifles remained about 1.5 MOA or worse depending on the load. This kept everything very simple as the AR10's are not the only 308 rifles I have. |
| My AR10’s all shoot 168 Amax fairly accurate. My bolt guns have there own though. Bolts guns can take top loads but AR10’s won’t be able to handle those loads unless you drop the charge for your bolt guns. Have tried doing what you’re wanting to do years ago. Better to separate your AR’s and bolt loads. Remember, your bolt actions are more accurate at longer distances. Up to you though. Good luck. |
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Personally, I would work up and independent load for the gas gun. That said, if your current bolt gun loads works and you are happy with the results so be it so long as you test the loads and deem them safe with no excessive ejector swipes marks or flattened primers. Try them in warm weather as well and use a chrono |
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I use the same load data in both a 175 SMK and a 165 sst in a 16 " DPMS , 165 SST 2550 fps. and the 175 SMK 2500 fps 44.0 Varget , CCI 250 M primer, LC brass @ 2800 aol rifle shoots with a good trigger pull right at moa . i use a CMC flat 2.5 lbs triggers in my LR308 i shoot it only with a YHM RK with a adjustable gas block |
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Maj. Richard Ayers
4-16-70
http://www.pownetwork.org/bios/a/a048.htm
Maj. Richard Ayers
4-16-70
http://www.pownetwork.org/bios/a/a048.htm
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Each of your AR10's are likely going to have slightly different headspace (if they're both the same, that's a definite bonus) but each barrel will have different harmonics. Not sure if the rifling is the same but unless you try to make each as similar as possible, same muzzle device, same torque ratings, etc...each will have a preferred load. Now the differences in load may be small enough that it's an acceptable compromise. And there's all sorts of small tricks to accuratize each. I agree on trying to keep things simple. I went way overboard, got a bit lost but learned a lot in the process. I think your current grouping is more than acceptable if you can do that on a regular basis. You're actually doing something right. Can it likely be improved? Yeah, probably, just depends on how much time you want to spend on it. I really go for "practical accuracy" as it's a gas AR and not a bolt gun, and it takes a lot of resources including time to get into the precision game. I'm never going to be able to shoot a .3 MOA group consistently out of an AR10. I don't separate bullets or cases by weight. I load LC brass with mixed headstamp (although I've begun separating it) and have really tried to limit myself to just a handful of projectiles. I'm currently building a 14.5" 6.5 Creedmoor using a POF Rogue as a base. I'm going to load for two projectiles only and try to stick to my guns. We'll see how that pans out. I will say I have half a dozen powders to try out to see what works best so it's always something. Given it's a shorter than normal barrel for 6.5CM, some experimentation is a requirement. I tend to stick with tangential ogive bullets for AR's as they're not really affected by jump to the lands. I also avoid bullets with plastic tips as they can deform when being chambered. I have a POF Revolution DI that, over the course of two factory barrels, has shot sub-MOA with hand loads. Bullet weight and powder, as you know, all have an effect. I've tried more than a dozen projectiles from 150 to 200 grain and have developed either close to or sub MOA accuracy for each. I've never had great luck with Varget and prefer IMR 4046 and lately, IMR 4895. With 4046 behind a Sierra 169 SMK in PMC or matched headstamp LC brass, I can consistently get sub-MOA results over 10 shots. I've never messed with seating depth and I load to just shy of mag length. I develop on a single stage and load in bulk on a progressive press, a Dillon 750 with a lot of afteramarket bits. This is a 10-shot group I shot recently, bulk-loaded on the Dillon with the Sierra 169 SMK's in PMC brass with CCI 34 primers. I can get similar results with their 155 Palma (the original version, not the new with a secant ogive) as well as with a cheap Hornady 150 grain FMJ (actually even smaller groups). So yeah, you can always improve but again it's a resource thing and what you're trying to do with the rifle. 
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There’s so much data and so many proven loads with .308 you really don’t have to do much other than work up, checking for pressure. Almost all of the work has been done for you by countless of others for decades. All you really have to do is pick a bullet, powder and see where most end up. Use that point as a reference and something to work up to while checking for pressure signs. Again there are so many documented loads that have been proven to be an accuracy node across many rifles. That’s the easy way and it’s safe… I look at what others have reported to be an accuracy node, work my way there. Once there I might play with COAL some but I have not noticed a tremendous difference in my semi autos but it’s been magic in my bolt guns. |
If a 147 grn 9mm at 1000 FPS is the hammer of Thor then a 165 grn. 40 at 1200 fps must a lightening bolt from Zeus!
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My .308 AR and the Scout Squad M1A share the same load. I went back and forth trying to get a generic load that works good for both. I have 3 50cal cans of pulled 172g M118 bullets. Got them from gibrass.com long ago. I use BL(C)-2 powder for that loading. I get really good accuracy from the 16" AR and pretty good accuracy from the Scout Squad. |
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Sic semper evello mortem tyrannis
Sic semper evello mortem tyrannis
| Many that work up loads do a Ladder Test to find accuracy nodes. Accuracy Nodes show you which of the powder charge weights are the most accurate. Working up a load isn't all about pressure signs, it's also about accuracy. There are lots of videos demonstrating loading for Ladder Tests. |
| Accuracy nodes are just that, they are charge weight with a specific bullet that has been proven to be accurate among a very wide range of rifles. That's why FGGM (other match rounds) are so accurate across many rifles. Yes, the powder they have isn't what we can get but the concept remains the same. Hornady used to use varget for their .308 match and their rounds ,they would tell you that and plus what the charge weight was per lot if you were unable take one apart. Amazingly it was the same accuracy nodes people report to using when handloading. |
If a 147 grn 9mm at 1000 FPS is the hammer of Thor then a 165 grn. 40 at 1200 fps must a lightening bolt from Zeus!
| I typically find an accurate load in my most accurate gun in that caliber and then check it in my others. So far my simple approach works OK because im fine with 1.5-2.5" groups in most guns. I like my heavier barreled rifles with 10x optics to shoot 1-1.5" pretty much with everything I load. |
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For cartridges like 223 and 308, there are many loads that work well in almost every rifle. Many of these rifles have very similar chambers, twists, lengths, etc. I agree that starting with one of these loads gets most people where they want to be. It’s worth testing a few until you find something that works well for you. Varget and a 175 SMK works well in lots of bolt and gas guns. |
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Originally Posted By bigkahuna48026: I’ve been thinking about reloading for two AR10s - S&W M&P 10 and PSA PA10. I’ve got a load developed for my bolt gun (175 gr SMK w/ 44.0 gr Varget) which I’d like to use for the sake of simplicity. I’ve tried a few rounds of this load and get about 1.5 MOA with no signs of over pressure in the ARs. However, from the reading I’ve been doing, I see some people saying each AR should have its own load developed. Some articles advise lowering the powder charge from bolt gun levels. Anyone got some real world experience that can share? Thanks Brass selection is key when loading .308. You can't use published load data when using Lake City brass, starting loads are at or even over maximum. A full 2.0 grain reduction is needed when using military brass. Commercial brass varies considerably as well. Some lots of Winchester brand brass weigh as little as 155 grains, usually never more than 160. Other brands run heavier, with Lake City and IMI weighing close to 180 grains empty and unprimed. This is the result of thicker case walls and thicker heads. I use the following loads which I consider maximum or near maximum in Lake City brass with 168 grain SMK's. Reduce these maximums by .5 grains when loading 175's. 41.5 grains of VihtaVuori N150 40.7 grains of IMR-4064 40.0 grains of IMR-4895 43.0 grains of WW-748 39.5 grains of H4895 41.0 grains of Varget 41.0 grains of RE-15 40.5 grains of AA-2460 These loads will achieve 2550 fps from most 24" barrels, subtract 100 fps for 20" barrels. They run approximately 2500 fps from a 22" M1-A. Many people load hotter than I do, but these loads are accurate and 100% reliable in my semi-auto rifles. Some pressure tested data exists that allows .5 to .8 grain higher charges than what I posted, but I get firing pin extrusions on my primers going higher than the loads I just posted, especially when using IMR-4064. |
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Originally Posted By borderpatrol: Brass selection is key when loading .308. You can't use published load data when using Lake City brass, starting loads are at or even over maximum. A full 2.0 grain reduction is needed when using military brass. Commercial brass varies considerably as well. Some lots of Winchester brand brass weigh as little as 155 grains, usually never more than 160. Other brands run heavier, with Lake City and IMI weighing close to 180 grains empty and unprimed. This is the result of thicker case walls and thicker heads. I use the following loads which I consider maximum or near maximum in Lake City brass with 168 grain SMK's. Reduce these maximums by .5 grains when loading 175's. 41.5 grains of VihtaVuori N150 40.7 grains of IMR-4064 40.0 grains of IMR-4895 43.0 grains of WW-748 39.5 grains of H4895 41.0 grains of Varget 41.0 grains of RE-15 40.5 grains of AA-2460 These loads will achieve 2550 fps from most 24" barrels, subtract 100 fps for 20" barrels. They run approximately 2500 fps from a 22" M1-A. Many people load hotter than I do, but these loads are accurate and 100% reliable in my semi-auto rifles. Some pressure tested data exists that allows .5 to .8 grain higher charges than what I posted, but I get firing pin extrusions on my primers going higher than the loads I just posted, especially when using IMR-4064. |
| I did load work ups with Varget for my LMT.308 with a 13.5” lightweight CB. I ended up at 44 grains under a Sierra 169 MK-CN which has a similar or slightly longer bearing surface to the 175 gn SMK. This load will shoot consistent moa or much tighter. It shows some pressure signs on new Winchester brass. I would not go higher even though Sierras manual shows a higher max. |
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Originally Posted By Ghostface: Accuracy nodes are just that, they are charge weight with a specific bullet that has been proven to be accurate among a very wide range of rifles. That's why FGGM (other match rounds) are so accurate across many rifles. Yes, the powder they have isn't what we can get but the concept remains the same. Hornady used to use varget for their .308 match and their rounds ,they would tell you that and plus what the charge weight was per lot if you were unable take one apart. Amazingly it was the same accuracy nodes people report to using when handloading. Different barrels do not necessarily display the same accuracy nodes. Barrels obviously DO NOT perform equally. THAT is the entire point of 'working up a load' AND doing a Ladder Test for each barrel. Doing so displays the MOST accurate load for that specific barrel. You could say statistically certain loads are more accurate for 'most barrels', but no one with knowledge and experience would say that a generic load would be ideal in comparison to the repeated accuracy one obtains with a worked up load chosen from a Ladder Test. |
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No one said all barrels perform equally but there is a reason why FACTORY MATCH ammo EXISTS and its because they PERFORM WELL across MOST rifles (barrels). The general consensus is if your rifle wont shoot with FGMM then you have a bad barrel. Now if you are talking about trying to get the absolute most and EXTREME accuracy then I agree with you to a degree but if EXTREME accuracy was the goal then we would not be shooting a semi now would we? |
If a 147 grn 9mm at 1000 FPS is the hammer of Thor then a 165 grn. 40 at 1200 fps must a lightening bolt from Zeus!
| Started reloading around 14 years ago. My AR10 308 was one of my 1st to reload for. Back then varget and 4064 was abundant. Also reloaded for my 308 bolt action. Varget worked superb for my bolt action with a 24 inch barrel, which Varget works very well in long barrels. 4064 did ok in the AR. Wasn’t great. Learned about 8208 so tried it. A great powder and works fantastic in all my AR10’s. If you haven’t tried 8208, give it a try. May surprise you. |
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