So SHOT has got me spending way too much money this year after falling in love with B&T's offerings at the ATAC range day. In the theme of appreciation for Swiss goodness, I'm convinced I need to add something from JDI's SAN offerings now as well. Since I'll be picking up a B&T APC223 with the intention of SBR'ing it, along with the much higher scarcity of the SAPR I've decided that the SAPR is the place to start. The question is do I go with one of the last remaining 14.3" barreled SAPRs or do I reserve one of the 16" or 20" SAPRs coming this year? I've already got a SCAR 17, which I'm in love with so I'm leaning towards the 14.3" barrel SAPR SB as it's a little shorter and a bit different. What sayeth SIGforum? Thanks

This message has been edited. Last edited by: Lt CHEG,

I hear you. I was bitten hard by the B&T bug and finally finished decking out my APC9 and GHM9 the way I want them with the Tailhook brace on a telescoping stock for the APC and the folding and Tailhook on the GHM. I really want the APC223 and a USW.
I’ve really wanted a real SAN after throwing so much cash at the early release of the Sig556. What a disappointment that was... The 751 is the grail but personally I wouldn’t be able to forgive myself for cutting the extended range of the 7.62 off at the knees by shortening the barrel. I can see it with the 5.56 but when I think of 7.62 I can only think of range. I don’t think I’d go any lower than 16” but that’s me. In the end though, you’re getting a 751 so I’m envious.

I elected for the 16" because I plan to run it suppressed and would prefer not to have to Form 1 it. Not all barrels have removable muzzle devices; some are integrated (20" for example, IIRC)

What kind of accuracy do you think I'd get out of a 20" barreled 751? The longest range I have that's convenient is 300 yards. Could I expect at least 1MOA at 300 yards with a 20" 751? I'm actually starting to have some second thoughts about the 14" 751, and actually I'm wondering if I should just get the 553. You've both brought up excellent points about the short barrel, but I also don't know that I want to spend so much on another .308 with the same barrel length as my SCAR 17. If the 751 will keep up with most of the higher end AR10's within reason (again not past 300 yards) then I might forego a later LMT purchase and have the 751 fulfill my SAN desire and a semi auto .308 DMR type rifle. Otherwise I'm almost leaning towards the 553, which I can shoot at the indoor range, and just have a broader range of short .223s that I can shoot at the indoor range that's only 7 minutes from my house and would likely get a ton more use. Ugh, decisions, decisions.

I have two 553's, a 551-2 and then the forthcoming 751 and 550 so I'm no help there LOL.

I will say....300yds is no issue on my 18" .223 Wylde SPR. I wouldn't dare use my 553 for that. a 751 with 16" + barrel will have no issues hitting 300 all day long.

I hear you about duplicating since you have the Scar17. I have one as well and had 2-16’s. I ended up moving the 16’s because, well, the 17 is the tits. Some people just dig those shorter barrel 7.62 beast blasters. I’m looking at the B&T APC223 pistol. Using my own advise I’d be wasting the potential range of the 5.56 also by getting a shorter barrel so don’t let that advice stop you. I’d love to have a 500, 551, or even a 552 but I think my first choice would be the 553. It’s on my list along with a FNC.

quote:

Originally posted by PGT:
I have two 553's, a 551-2 and then the forthcoming 751 and 550 so I'm no help there LOL.

I will say....300yds is no issue on my 18" .223 Wylde SPR. I wouldn't dare use my 553 for that. a 751 with 16" + barrel will have no issues hitting 300 all day long.

Would you prioritize a 553 over a 751 since you have 2 of them lol? I'm actually quite tempted at one of the FDE 553 pistols that JDI has in stock right now. I struggle somewhat because the 751 will definitely be more collectible and rare, but I also know that just like my SCAR 17 vs my SCAR 16, a 751 would get shot much less than a 553 because I shoot indoors much more often than outdoors and I can only go up to .223 indoors. I like having rare things but I also like enjoying what I have.

quote:

Originally posted by 10X-Shooter:
I hear you about duplicating since you have the Scar17. I have one as well and had 2-16’s. I ended up moving the 16’s because, well, the 17 is the tits. Some people just dig those shorter barrel 7.62 beast blasters. I’m looking at the B&T APC223 pistol. Using my own advise I’d be wasting the potential range of the 5.56 also by getting a shorter barrel so don’t let that advice stop you. I’d love to have a 500, 551, or even a 552 but I think my first choice would be the 553. It’s on my list along with a FNC.

I'm totally buying the APC 223 pistol, it's awesome. I also think short .223 rifles are much more practical because it seems like you lose much less by going super short with a .223 vs a .308. There's definitely a compromise but it seems like a much smaller compromise.

quote:

Originally posted by Lt CHEG:
I also think short .223 rifles are much more practical because it seems like you lose much less by going super short with a .223 vs a .308. There's definitely a compromise but it seems like a much smaller compromise.

Do you have data to back up your premise of 223 vs. 308 ballistics?

Granted, quality data in the web for MV of shorter rifles can be spotty. I'm going by memory, as I can't dive into things right now, but I recall that the percentage of MV lost per inch of barrel lost is relatively similar for the two calibers.

quote:

Originally posted by fritz:

quote:

Originally posted by Lt CHEG:
I also think short .223 rifles are much more practical because it seems like you lose much less by going super short with a .223 vs a .308. There's definitely a compromise but it seems like a much smaller compromise.

Do you have data to back up your premise of 223 vs. 308 ballistics?

Granted, quality data in the web for MV of shorter rifles can be spotty. I'm going by memory, as I can't dive into things right now, but I recall that the percentage of MV lost per inch of barrel lost is relatively similar for the two calibers.

My data is purely anecdotal, I really don't have any particular numbers. Having said that, even if .223 and .308 barrels lose velocity with similar proportions when going shorter I still believe that you lose more with a .308. My reasoning is that .308 is generally better at more extended ranges than .223 to begin with so shorter barrels tend to lose more in my opinion. Also, again anecdotally, it seems like muzzle blast seems even worse with shorter .308 rifle barrels. That's my view at least.

quote:

Originally posted by Lt CHEG:
My data is purely anecdotal, I really don't have any particular numbers. Having said that, even if .223 and .308 barrels lose velocity with similar proportions when going shorter I still believe that you lose more with a .308. My reasoning is that .308 is generally better at more extended ranges than .223 to begin with so shorter barrels tend to lose more in my opinion. Also, again anecdotally, it seems like muzzle blast seems even worse with shorter .308 rifle barrels. That's my view at least.

I don't think you understand bullet flight ballistics. 223 bullets have noticeably lower ballistic coefficients ("BC") than 308 bullets, for normal & comparable bullet weights. This means that regardless of starting velocities, a higher BC bullet retains velocity better than a lower BC bullet. The following are sample G1 BCs for common bullets:

223:
55 FMJ = .250
55 Vmax = .255
69 SMK = .317
77 SMK = .362
75 HPBT = .395
73 ELD-M = .395

308:
150 FMJ = .398
168 Amax = .475
168 SMK = .462
175 SMK = .505

This means that one of the worst 308 bullets retains velocity better than most of the best 223 bullets.

There's quite a bit of data on 223 barrel lengths versus muzzle velocity. For grins, let's look at 8" and 10" barrels in comparison to 18" barrels.

Ballistics by the inch site, for 55 grain FMJ:
8" is 80% MV of 18"
10" is 88% MV of 18"

Rifle shooter site, for 55 FMJ:
8" is 76% MV of 18"
10" is 83% MV of 18"

Rifle shooter site, for 68 match:
8" is 79% MV of 18"
10" is 86% MV of 18"

Guns & ammo site, for 62 Barnes TSX:
8" is 78% MV of 18"
10" is 84% MV of 18"

Rifle shooter site is one of the few sites that compares MV for 308 barrels shorter than 16". Combining a couple of their barrel chopping analysis articles:
for 168 SMK:
8" is 76% MV of 18"
10" is 84% MV of 18"

for 147 FMJ:
8" is 76% MV of 18"
10" is 83% MV of 18"

Granted, the 223 muzzle velocities tend to be a little higher than those of the 308 bullets (especially for the lighter bullets), but the MVs of both calibers are quite similarly affected by changing their barrel lengths.

quote:

Originally posted by fritz:

quote:

Originally posted by Lt CHEG:
My data is purely anecdotal, I really don't have any particular numbers. Having said that, even if .223 and .308 barrels lose velocity with similar proportions when going shorter I still believe that you lose more with a .308. My reasoning is that .308 is generally better at more extended ranges than .223 to begin with so shorter barrels tend to lose more in my opinion. Also, again anecdotally, it seems like muzzle blast seems even worse with shorter .308 rifle barrels. That's my view at least.

I don't think you understand bullet flight ballistics. 223 bullets have noticeably lower ballistic coefficients ("BC") than 308 bullets, for normal & comparable bullet weights. This means that regardless of starting velocities, a higher BC bullet retains velocity better than a lower BC bullet. The following are sample G1 BCs for common bullets:

223:
55 FMJ = .250
55 Vmax = .255
69 SMK = .317
77 SMK = .362
75 HPBT = .395
73 ELD-M = .395

308:
150 FMJ = .398
168 Amax = .475
168 SMK = .462
175 SMK = .505

This means that one of the worst 308 bullets retains velocity better than most of the best 223 bullets.

You make an excellent point and I'm far from an expert at long distance shooting. It makes sense that the .308 would retain velocity better, but I think my point was that if I was looking to shoot greater distances a .223 would not be my first choice because of its limitations. So in effect, losing longer range abilities, even proportionately worse due to poorer BC, wouldn't be as much of a factor since I think of .223 as more of a CQB caliber. Any loss of ballistic performance with a .308 makes it less appealing to me since the biggest reason for me to pick a .308 over a .223 would be primarily for distance.

I'm probably not expressing myself well, but in sum and substance my thoughts are that .223s are more CQB oriented while .308s are more distance oriented. The increased blast from a short .308 unquestionably makes it less enjoyable to shoot in my opinion. And I guess as it refers to the SAPR in question, as cool as it is, it is expensive and I'm just not sure it's going to shoot as accurately as an LMT MWS or possibly even an HK762. The question for me ultimately, would the SAPR in any of its iterations shoot as accurately or moreso than an LMT? The higher weight of the SAPR makes it less likely that I would choose it for more CQB type blasting (that would require a .308) over the SCAR 17. I admire its reliability and robustness but if I feel like I'm leaving a lot on the table in distance accuracy over an LMT or perhaps a possible civilian HK CSASS then it would be harder for me to pick the SAPR.

In reality I really want a 553 and a SAPR as well as the B&T APC 223 and 556 as well as the USW. I don't think I can afford to drop $15k on guns this year so I've got to figure out what I want most for the collection. I've got a very limited opportunity to pickup multiple B&T's at a greatly discounted price so I'm definitely buying at least 2 of those this year. However nobody knows how long the JDI SAPRs will last or for that matter how long they'll want to continue bringing the 553s in so there's that to consider too. I know, first world problems, but it does make for a tough decision.

quote:

Originally posted by Lt CHEG:
Any loss of ballistic performance with a .308 makes it less appealing to me since the biggest reason for me to pick a .308 over a .223 would be primarily for distance.

Again, you don't understand flight ballistics well -- 308 bullets exhibit superior velocity retention over comparable 223 bullets, at all distances. The 223 has a relatively greater loss of ballistic performance from the moment the bullet exits the barrel. I do not understand how you consider the 308 "less appealing" at any distance, based on a "loss of ballistic performance". Although 308 bullets do not exhibit the flight efficiency of many 6mm to 7mm bullets, 308 bullets are noticeably more efficient than 223 bullets.

At really short distances the BC differences among bullets don't make much difference to relative velocity retention. But never is a 308 bullet at a disadvantage to a 223 bullet.

Now from a muzzle blast standpoint, I find unsuppressed short barrel 223 and 308 equally unpleasant. Suppressed, they're both reasonable.

From a recoil standpoint, the 223 is much more reasonable to shoot -- its recoil energy is generally in the 20% to 25% ballpark of that of a 308, for comparable rifles and standard loads.

quote:

Originally posted by fritz:

quote:

Originally posted by Lt CHEG:
Any loss of ballistic performance with a .308 makes it less appealing to me since the biggest reason for me to pick a .308 over a .223 would be primarily for distance.

Again, you don't understand flight ballistics well -- 308 bullets exhibit superior velocity retention over comparable 223 bullets, at all distances. The 223 has a relatively greater loss of ballistic performance from the moment the bullet exits the barrel. I do not understand how you consider the 308 "less appealing" at any distance, based on a "loss of ballistic performance". Although 308 bullets do not exhibit the flight efficiency of many 6mm to 7mm bullets, 308 bullets are noticeably more efficient than 223 bullets.

At really short distances the BC differences among bullets don't make much difference to relative velocity retention. But never is a 308 bullet at a disadvantage to a 223 bullet.

Now from a muzzle blast standpoint, I find unsuppressed short barrel 223 and 308 equally unpleasant. Suppressed, they're both reasonable.

From a recoil standpoint, the 223 is much more reasonable to shoot -- its recoil energy is generally in the 20% to 25% ballpark of that of a 308, for comparable rifles and standard loads.

I understand that the .308 is ballistically superior to the .223 at all barrel lengths, and is a better choice at distance than the .223 particularly when both barrels are shortened from what is usually seen. At longer distances, admittedly longer than I plan on shooting these rifles, it's my understanding that the .308 really relies upon higher velocity because it's BC is much poorer than the more modern 6.5 and 6.0 mm cartridges. I guess my thought was that the .308 would be more drastically affected by a shorter barrel than it actually is so thank you for helping to show me that.

Having said that would you feel like a shorter SAPR is a good choice? If you were in my shoes would you pick a 14", 16" or 20" barreled SAPR? The only actual shooting of SAPRs that I've seen has been on Larry Vickers' YouTube channel. He has his personal 751 setup with an aimpoint instead of a magnified optic,so I guess in my head it has me thinking that the 14" barreled SAPR gives up more in long range ability than it actually does. I do appreciate you sharing your knowledge and I apologize for my poor usage of vocabulary surrounding distance shooting. There is supposed to be a 1200 yard and 2100 yard shooting range opening up in the next year about an hour from my house so I hope that I'll be able to get more into distance shooting in the future. I actually really enjoyed shooting at the 600 to 900ish yard targets at the range before SHOT. I was doing pretty well at the longer distances so I sort of understand how I need to use the equipment to hit targets at distance, I'm just pretty ignorant of what equipment to pick for myself.

Iirc, with the 55x series pistols, there is an issue with removing the gas plug for cleaning when you have a suppressor mount. I am guessing that same issue impacts the SAPR. Is there a general workaround for this? Is there a can and mount combo that works on these guns?

quote:

Originally posted by Lt CHEG:
The only actual shooting of SAPRs that I've seen has been on Larry Vickers' YouTube channel. He has his personal 751 setup with an aimpoint instead of a magnified optic,so I guess in my head it has me thinking that the 14" barreled SAPR gives up more in long range ability than it actually does.

LV's youtube on the 751 is unremarkable IMO. So here he has this "precision rifle" (the "PR" in SAPR), and he's banging away on a reduced-size IPSC offhand at maybe 25 yards. I guess the slow motion footage shows the "precision" aspect. Honestly, even Hi Point carbines can do what is on that video.

You state you have a SCAR-17 and an SBR 223. Are you looking to add redundancy here? If so, the 14" 751 likely works. Are you looking for additional capabilities at more distant targets? The longer barrel 751s will be more appropriate, but maybe at only an incremental level.

From an accuracy standpoint, I suspect the 751 will be a little more accurate than your SCAR. IMO SCARs shoot fine when they're cold, but maybe due to the thin barrel profile, their accuracy suffers as the gun heats up. FN builds the SCAR to be what they call a battle rifle, yet in the heat of battle, the rifle's accuracy deteriorates.

Will a 751 hang with an AR-10 in accuracy -- to 300 yards and beyond? Good question. I see no way the 751 is in the league of the true precision ARs from the likes of GAP, JP, LaRue, and Knights. Probably not in the league of the next tier of AR-10s either. But all this depends upon what you consider reasonable accuracy. Consistent (not once in a blue moon) 1 MOA to 300 yards? I wouldn't bet in favor or the 751, although it might be close with the right ammo and good shooting.

You mention longer distances -- 600, 900, 1200 yards. Again, depends on your accuracy demands. Banging away at a full sized IPSC at 600? There are a lot of rifles and carbines that can do that. Do it well enough to choose which part of the plate the impact will occur. Consistently hitting a IPSC at 1200 in any conditions? A whole different ball game, and one that semi-auto rifles are at a disadvantage. For that matter, any gun chambered in 308 is challenged at 1200 -- I know, as I shoot my bolt action 308 at similar distances at an ongoing basis.

I recommend defining your realistic shooting requirements, then evaluating options based on a given firearm's capabilities.

I'm still torn, but my decision got somewhat easier. The last 20" SAPR is gone, so it's either a 14" or 16" SAPR if I still choose to go that route. The biggest difference is whether or not I want a permanent or removable flash hider. I'm leaning towards the 14" if I go with a SAPR. I figure I like the looks better and if I wanted to suppress it, I should be able to use a B&T Rotex suppressor I think. What's everyone think with this new development? Thanks

16's are removable, no?

quote:

Originally posted by PGT:
16's are removable, no?

Correct. 16" barrels have removable flash hiders, the 14" barrel flash hiders are milled into the barrel. I'm pretty sure the permanent barrels are NATO standard though, so my assumption was the B&T Rotex would work. Is that assumption not correct?