Tika58. The 1-7 twist being for heavier bullets, delights in fodder at pills above 60grs. I have used several different brands and grain weights. Sometimes a little experimentation will result in stellar performance. Each barrel will decide it’s preferences only to be determined on the firing line. With more conclusive result exposed in the field.
An excellent hog pill has been the Barnes 70gr running above 2800fps. Well noted this round performs best at 150yds or less. Speed is the issue for bullet performance. Perfect mushrooms need the higher velocities that are lacking at longer distances.
The 40gr versions will not benefit from a 1-7 twist. As others have stated, you will have to slow em down. Simply no need for a fast twist on small versions. The other bad thing you get is higher pressures at faster twists accompanied with higher velocities even in the lower grain spectrum. While not endangering yourself with blowing up your AR, the little bullets have been known to blow up or simply come apart at high velocities and fast twists. Other things as erratic patterns let alone any group attempt.
Hence bullet makers labeled some bullets as such. My 22 Hornet bullets need to be segregated from bullets designated for 223 chambers.
Depending upon the range of your intended target and the target itself,, you may be able to use the 40 gr at say a medium velocity, with positive results. I have seen decent groups at 100 yds and then when the attempt to stretch the legs, resulted in patterns and flyers.
I suggest a ladder load since the limits of components is strangling.