Has anyone tried this bullet out? https://www.midwayusa.com/product/10...-tip-boat-tail
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Has anyone tried this bullet out? https://www.midwayusa.com/product/10...-tip-boat-tail
Didn't even realize that had a 60....I use both the 69 and 77 with great success.
Just ordered 200 60 gr TMKs.
The 69 and 77 TMKs work great in my 1:8 twist .223 but my 1:9 doesn't shoot 69 gr bullets very well and the 77 gr TMKs won't stabilize.
I have also had great results with TMKs in my .308s and in my 6.5mm Creedmoor rifles.
I intend to try the 60 gr TMKs in my 1:9 twist and of course I will try them in my 1:8 twist just to compare them with the 69 and 77 TMKs.
One thing I found was that the TMKs shoot best when they are loaded out about 0.070 to 0.080 longer than the standard SMKs.
The 2.330 O.A.L. fits in a Savage bolt action mag but not in an AR mag.
In my 1:8 twist Les Baer Super Varmint .223 AR rifle I have to use a single round follower because the seated out TMKs won't fit in an AR magazine.
I am going to wait for the weather to turn a bit warmer before I try the 60 gr TMKs.
It was around 20 degrees in the AM at our range this past week.
That is a bit to cold for an old geezer like me.
I will be curious to see what COAL you get with the 60s...I only use the 69/77s in my bolt guns cause they are so long. And the GameChangers are even *longer*.
Let us know the length of the bullet. .323 bc on these, standard 69MK is .301. Both are for 10 twist or faster.
Bullet data compared to a 69 TMK and 69 SMK:
The 60 TMK # 7160 base to tip is .900 inches (BC =0.323).
The 69 TMK # 7169 is 0.985 inches (BC = 0.375).
The 69 SMK # 1380 is 0.892 inches BC=0.301).
Boat tail length is the same as the 69 TMK #7169 and 69 SMK #1380.
Thanks! Hope they shoot itty bitty groups.
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Finally got to the range with some 60 grain TMK loads for my Les Baer Super Varmint .223 with a 1:8 twist, 18-inch, 416R stainless steel barrel with a Bushnell 6500 Elite 4.5-30x50mm scope at 100 yards.
Here are the results for 3 5-round groups with 3 different loads.
I used H4895 powder all with the same charge but varied seating depth to get the same bullet velocity (also barrel exit time) given slightly different trim lengths in the brass I used and based upon the forecasted rising temperatures.
The perfect exit time would have been 1.0493, but given the temperature at the time I shot was a few degrees off what I loaded for so the exit time was 0.0013 msec. off.
The velocity was close enough to have the blast reflection just about at the bolt face so the barrel crown was the tightest when the bullet exited.
# Groups Hand Load data
Lapua Brass, CCI BR-4 primers, exit time 1.048 msec.
Powder, Charge, O.A.L., bullet, velocity, trim length, tempBullet Bullet Weight (Grains) Velocity FPS Group (in.) 3-Shots % Minutes of Angle Avg Group (in.) 5 shots % Minutes of Angle # Groups Mean Std Dev Grp 1 Grp 2 Grp 3 3 H4895 24.6 gr 2.330 O.A.L. 60 TMK 3132 case 1.758 51/47 deg F. Sierra Tipped Match King #7160 60 3132 0.208 19.9% 0.309 29.5% 3 0.329 0.093 0.208 0.329 0.390 3 H4895 24.6 gr 2.331 O.A.L. 60 TMK 3132 case 1.755 53/49 deg F. Sierra Tipped Match King #7160 60 3132 0.293 28.0% 0.347 33.1% 3 0.316 0.075 0.293 0.316 0.432 3 H4895 24.6 gr 2.333 O.A.L. 60 TMK 3132 case 1.758 53/50 deg F. Sierra Tipped Match King #7160 60 3132 0.303 28.9% 0.388 37.1% 3 0.356 0.105 0.303 0.356 0.506 Winds were dead calm for the first load and rose slightly as the temperature rose. However, I rushed shooting the last group in the last load to get the group in before a scheduled cease fire.
Even then, the average group sizes were pretty close and the overall average was 0.348 for 9 groups.
Quite the combo. Nice shooting.
Also shot two loads with H4895 powder and 60 grain TMK bullets with my 1:9 twist bolt action CZ 527 varmint .223 with 24 inch barrel.
This rifle shoots 52 and 53 grain bullet best.
These 10 groups averaged 0.470.
# Grps Powder, Charge, O.A.L, bullet, Vel, trim, primer, exit time, brass, temp Bullet Type Wgt. Vel. Best Grp % of MOA Avg. % MOA Median St Dev Grp #1 Grp #2 Grp #3 Grp #4 Grp #5 5 H4895 21.4 gr 2.317 60 TMK #7160 2732 trim 1.758 Rem 7.5 wf 1.256 * Hornady 45/40 deg F. Sierra #1760 60 gr TMK 60 2732 0.302 0.288 0.471 0.450 0.522 0.130 0.302 0.370 0.522 0.544 0.617 5 H4895 21.4 gr 2.315 60 TMK #7160 2732 trim 1.755 Rem 7.5 wf 1.256 * Hornady 47/42 deg F. Sierra #1760 60 gr TMK 60 2732 0.191 0.182 0.468 0.447 0.534 0.193 0.191 0.352 0.534 0.612 0.652
For comparison, the average with Hornady # 2270 60 grain bullets was 0.773 and Sierra #1375 60 grain bullets averaged 0.610 for 50 groups.
The 69 TMKs averaged 0.499 for 27 groups.
Conditions were slightly colder than for the tests above with the Les Baer .223. I shot these loads first when the temperature was between 40 and 42 degrees, even though the temps were forecasted to be between 45 and 47 degrees. Winds were calm.
Now you know why I like TMKs.
The CZ 527 is a nice rifle that cost about $625 about 6 years ago but now has almost 7,000 rounds down the barrel and I think is feeling its age. It has a Kevlar stock and a set trigger that is now shooting just above 1 lb. That is a bit light for a very light rifle, even from a bench and I had to be very careful with it.